U.S. patent application number 10/961779 was filed with the patent office on 2006-04-13 for power transmission fluids with enhanced antishudder durability and handling characteristics.
This patent application is currently assigned to AFTON CHEMICAL CORPORATION. Invention is credited to Nubar Ozbalik.
Application Number | 20060079412 10/961779 |
Document ID | / |
Family ID | 35519740 |
Filed Date | 2006-04-13 |
United States Patent
Application |
20060079412 |
Kind Code |
A1 |
Ozbalik; Nubar |
April 13, 2006 |
Power transmission fluids with enhanced antishudder durability and
handling characteristics
Abstract
A finished power transmitting fluid having enhanced friction
durability and improved .mu./v characteristics on paper, steel and
advanced friction materials such as carbon fiber, and which may
provide a lubricant composition that carries minimal concern for
skin sensitization and related health, safety, and environmental
issues, can contain lubricating base oil, a friction modifier
produced by reacting a polyamine with an aliphatic mono acid such
as oleic or isostearic acid under conditions to form a mixture of
1,2-disubstituted imidazoline containing components, wherein
further acylation of residual active nitrogens with mono or diacids
or anhydrides affords friction modifier compositions having
enhanced frictional and handling characteristics.
Inventors: |
Ozbalik; Nubar; (Midlothian,
VA) |
Correspondence
Address: |
DENNIS H. RAINEAR
CHIEF PATENT COUNSEL, ETHYL CORPORATION
330 SOUTH FOURTH STREET
RICHMOND
VA
23219
US
|
Assignee: |
AFTON CHEMICAL CORPORATION
|
Family ID: |
35519740 |
Appl. No.: |
10/961779 |
Filed: |
October 8, 2004 |
Current U.S.
Class: |
508/283 ; 252/77;
252/78.1; 508/285 |
Current CPC
Class: |
C10M 2215/224 20130101;
C10M 133/44 20130101; C10N 2040/044 20200501; C10N 2040/04
20130101; C10M 135/32 20130101; C10M 2219/09 20130101; C10N
2040/045 20200501; C10M 141/08 20130101; C10N 2020/01 20200501;
C10M 2205/173 20130101; C10M 141/06 20130101; C10N 2040/042
20200501 |
Class at
Publication: |
508/283 ;
508/285; 252/077; 252/078.1 |
International
Class: |
C10M 133/46 20060101
C10M133/46 |
Claims
1. A fluid composition, comprising: (1) a major amount of a base
oil, and (2) a minor amount of an additive comprising: (i) a
reaction product of an aliphatic carboxylic acid and a polyamine
obtained under conditions sufficient to produce a mixture
containing one or more compounds represented by formula I and/or
II; (ii) a reaction product obtained by (a) reacting an aliphatic
carboxylic acid and a polyamine under conditions sufficient to
produce a mixture of 1,2-disubstituted imidazolines containing one
or more compounds represented by formula I and/or II, and then (b)
treating under conditions to produce a further mixture containing
one or more compounds represented by formula III, IV, V and/or VI;
or (iii) a mixture containing at least one compound represented by
formula I and/or II and at least one compound from among the
compounds represented by formulas III to VI, wherein said formulas
are: ##STR7## wherein R.sub.1 and R.sub.2 are independent of one
another and represent C.sub.3 to C.sub.30 straight or branched
alkyl, alkenyl or aryl or heteroatom derivatives thereof, such as
an alkyl having heteroatoms, as one example; R.sub.3 and R.sub.4
are independent of one another and are selected from the group
consisting of H, --OH, --OR, --COOH, --SH, --SR, straight chain,
branched alkyl, alkenyl radicals and hydrocarbyl groups in
oligomeric or polymeric form that are derived from propylene,
isobutylene and higher olefins having terminal, internal and
vinylidene double bonds, R represents an alkyl or alkenyl group
having up to 30 carbon atoms in linear, branched or cyclic form and
n is a value from 0 to 5.
2. The fluid composition of claim 1, wherein the additive contains
a compound represented by formula I and a compound represented by
formula II.
3. The fluid composition of claim 1, wherein the additive contains
a compound represented by formula I, a compound represented by
formula II, and a compound represented by formula III and a
compound represented by formula IV.
4. The fluid composition of claim 1; wherein the additive contains
a compound represented by formula I, a compound represented by
formula II, a compound represented by formula V and a compound
represented by formula VI.
5. The fluid composition of claim 1, wherein the additive contains
a compound represented by formula III and a compound represented by
formula IV.
6. The fluid composition of claim 1, wherein the additive contains
a compound represented by formula V and a compound represented by
formula VI.
7. The fluid composition of claim 1, wherein said additive
comprises a mixture containing at least one compound represented by
formula I or II and at least one compound from among the compounds
represented by formulas III to VI.
8. The fluid composition of claim 1, wherein the base oil comprises
one or more of a natural oil, a mixture of natural oils, a
synthetic oil, a mixture of synthetic oils, a mixture of natural
and synthetic oils, and a base oil derived from a Fischer-Tropsch
or gas-to-liquid process.
9. The fluid composition of claim 1, wherein the base oil has a
kinematic viscosity of from about 2 centistokes to about 10
centistokes at 100.degree. C.
10. The fluid composition of claim 1, wherein the fluid composition
contains an ashless dispersant.
11. The fluid according to claim 1 or 10, wherein said fluid
composition contains at least one a detergent, another friction
modifier, an antioxidant, an antiwear agent, an antifoam agent, a
viscosity index improver, a copper corrosion inhibitor, an
anti-rust additive, a seal swell agent, and/or a metal
deactivator.
12. The fluid composition of claim 1, wherein the additive is
present in an amount of about 0.01 wt. % to about 10 wt. %, based
on the fluid composition.
13. The fluid composition of claim 1, wherein the additive is
present in an amount of from 0.1 wt. % to 5.0 wt. %.
14. A transmission containing the fluid composition of claim 1.
15. The transmission of claim 14, wherein the transmission
comprises a continuously variable transmission.
16. The transmission of claim 14, wherein the transmission
comprises a dual clutch transmission.
17. The transmission of claim 14, wherein the transmission
comprises an automatic transmission.
18. The transmission of claim 14, wherein the transmission
comprises a manual transmission.
19. The fluid composition of claim 1, wherein the fluid is adapted
for use in a transmission employing one or more of an
electronically controlled converter clutch, a slipping torque
converter, a lock-up torque converter, a starting clutch, and one
or more shifting clutches.
20. The fluid composition of claim 1, wherein the fluid is adapted
for use in a belt, chain, or disk-type continuously variable
transmission, a 4-, 5-, 6-, or 7-speed automatic transmission, a
manual transmission, an automated manual transmission, or a dual
clutch transmission.
21. The fluid composition of claim 1, wherein the fluid is adapted
for use in an industrial gear or an automotive gear.
22. A vehicle comprising an engine and a transmission, the
transmission including the fluid of claim 1.
23. A vehicle comprising a differential, the differential including
a lubricant containing the fluid composition of claim 1.
24. A method for producing friction modifier compounds comprising:
(a) reacting a molar excess of at least one carboxylic acid
R.sub.1COOH with a linear polyamine represented by the formula
H.sub.2N--(CH.sub.2CH.sub.2NH).sub.x--CH.sub.2, where x represents
an integer of 1 to 10 at a temperature in a range of about
120.degree. C. to about 180.degree. C. for about 5 to about 20
hours, said compounds being represented by formula I and II
##STR8## wherein R.sub.1 represents a C.sub.3 to C.sub.30 straight
or branched alkyl, alkenyl or aryl or heteroatom derivative
thereof, and n is a value from 0 to 5.
25. A method for producing friction modifier compounds according to
claim 24, wherein R.sub.1 represents --C.sub.17H.sub.35.
26. A method for producing friction modifier compounds according to
claim 24, wherein said molar ratio of carboxylic acid to polyamine
is about 1:1 to about 2:1.
27. A method for producing friction modifier compounds according to
claim 26, wherein said molar ratio is about 1.2:1 to about
1.6:1.
28. A method for producing friction modifier compounds according to
claim 27, wherein said molar ratio of carboxylic acid to polyamine
is about 4:3.
29. A method for producing friction modifier compounds according to
claim 24, wherein the reaction is for about 12 to about 16
hours.
30. A method for producing friction modifier compounds according to
claim 25, wherein the reaction temperature is about 150.degree.
C.
31. A method for producing friction modifier compounds according to
claim 24, wherein said method yields a reaction product in which
there is a ratio of at least one compound represented by formula I
to at least one compound represented by formula II of about
2:1.
32. A method for producing friction modifier compounds according to
claim 24, wherein said method further comprises post treating the
reaction products from (a) with at least one carboxylic acid
R.sub.2COOH in an amount that at least a portion of the reactive
nitrogen atoms in a compound of formula I or II can be acylated,
whereby a compound(s) represented by formula III and a compound(s)
represented by formula IV are obtained: ##STR9## wherein R.sub.1
and R.sub.2 are independent of one another and represent C.sub.3 to
C.sub.30 straight or branched alkyl, alkenyl or aryl groups or a
heteroatom derivative thereof.
33. A method for producing friction modifier compounds according to
claim 24, wherein said method further comprises post-treating a
reaction product comprising at least one compound represented by
formula I and at least one compound represented by formula II with
at least one organic acid or an anhydride thereof in an amount that
at least a portion of the nitrogens in said compounds can be
acylated, whereby compounds represented by formulas V and VI are
obtained: ##STR10## wherein R.sub.3 and R.sub.4 can be independent
of one another and represent C.sub.3 to C.sub.30 straight or
branched alkyl, alkenyl or aryl groups or a heteroatom derivative
thereof; R.sub.3 and R.sub.4 can be independent of one another and
are selected from the group consisting of H, --OH, --OR, --COOH,
--SH, --SR, straight chain, beta branched alkyl, alkenyl radicals
and hydrocarbyl groups in oligomeric or polymeric form that are
derived from propylene, isobutylene and higher olefins having
terminal, internal and vinylidene double bonds, wherein R is an
organic group having up to 30 carbon atom, and n is a value from 0
to 5.
34. A method for providing improved durability of friction
characteristics in a lubricated power transmitting apparatus
comprising: 1) adding a fluid to an power transmitting apparatus,
said fluid comprising (a) a base oil, and (b) a friction modifier
comprising (i) a reaction product of an aliphatic carboxylic acid
and a polyamine, said reaction product obtained under conditions
sufficient to produce a mixture of 1,2-disubstituted imidazolines,
said mixture containing one or more compounds represented by
formula I and/or II, (ii) a reaction product obtained by (a)
reacting an aliphatic carboxylic acid and a polyamine, said
reaction product obtained under conditions sufficient to produce a
mixture of 1,2-disubstituted imidazolines, said mixture containing
one or more compounds represented by formula I and/or II, and then
(b) treating under conditions to provide at least one or more
compounds represented by formula III, IV, V and/or VI; or (iii) a
mixture containing at least one compound represented by formula I
or II and at least one compound from among the compounds
represented by formula III, IV, V or VI: ##STR11## wherein R.sub.1
and R.sub.2 are independent of one another and are represent
C.sub.3 to C.sub.30 straight or branched alkyl, alkenyl or aryl or
heteroatom derivatives thereof; R.sub.3 and R.sub.4 are independent
of one another and are selected from the group consisting of H,
--OH, --OR, --COOH, --SH, --SR, straight chain, beta branched
alkyl, alkenyl radicals and hydrocarbyl groups in oligomeric or
polymeric form that are derived from propylene, isobutylene and
higher olefins having terminal, internal and vinylidene double
bonds, R represents an organic group having up to 30 carbon atoms,
and n is a value from 0 to 5; and 2) operating the fluid in the
power transmitting apparatus, wherein the duration of stability
against oxidation of said fluid as a power transmission fluid is
improved relative to the performance of a transmission without said
fluid.
35. The method of claim 34, wherein the base oil has a kinematic
viscosity of from about 2 centistokes to about 10 centistokes at
100.degree. C.
36. The method of claim 34, wherein the fluid further comprises an
ashless dispersant.
37. The method according to claim 34 or 36, wherein said fluid
further comprises at least one member selected from the group
consisting of an antioxidant, an antifoam agent, an antiwear agent,
an antirust additive, a detergent, a viscosity index improver, a
copper corrosion inhibitor, a seal swell agent, a metal
deactivator, and a friction modifier other than one represented by
formulas I to VI.
38. The method of claim 34, wherein the power transmitting
apparatus comprises a transmission.
39. The method of claim 34, wherein the power transmitting
apparatus comprises an industrial gear or an automotive gear.
40. An additive composition comprising: (1) (i) a reaction product
of an aliphatic carboxylic acid and a polyamine obtained under
conditions sufficient to produce a mixture containing one or more
compounds represented by formula I and/or II; (ii) a reaction
product obtained by (a) reacting an aliphatic carboxylic acid and a
polyamine under conditions sufficient to produce a mixture of
1,2-disubstituted imidazolines containing one or more compounds
represented by formulas I and/or II, and then (b) treating under
conditions to produce a further mixture containing one or more
compounds represented by formula III, IV, V and/or VI; or (iii) a
mixture containing at least one compound represented by formula I
and/or II and at least one compound from among the compounds
represented by formulas III to VI, wherein said formulas are:
##STR12## wherein R.sub.1 and R.sub.2 are independent of one
another and represent C.sub.3 to C.sub.30 straight or branched
alkyl, alkenyl or aryl or heteroatom derivatives thereof; R.sub.3
and R.sub.4 are independent of one another and are selected from
the group consisting of H, --OH, --OR, --COOH, --SH, --SR, straight
chain, beta branched alkyl, alkenyl radicals and hydrocarbyl groups
in oligomeric or polymeric form that are derived from propylene,
isobutylene and higher olefins having terminal, internal and
vinylidene double bonds, R represents an organic group having up to
30 carbon atoms and n is a value from 0 to 5.
41. A method for improving the handling characteristics of a power
transmission fluid comprising adding thereto an additive according
to claim 40.
42. A fluid composition, comprising: (1) a major amount of a base
oil, and (2) a minor amount of an additive comprising: (i) a
mixture containing one or more compounds represented by formula I
and/or II; or (ii) a mixture containing at least one compound
represented by formula I and/or II and at least one compound from
among the compounds represented by formulas III to VI, wherein said
formulas are: ##STR13## wherein R.sub.1 and R.sub.2 are independent
of one another and represent C.sub.3 to C.sub.30 straight or
branched alkyl, alkenyl or aryl or heteroatom derivatives thereof,
such as an alkyl having heteroatoms, as one example; R.sub.3 and
R.sub.4 are independent of one another and are selected from the
group consisting of H, --OH, --OR, --COOH, --SH, --SR, straight
chain, branched alkyl, alkenyl radicals and hydrocarbyl groups in
oligomeric or polymeric form that are derived from propylene,
isobutylene and higher olefins having terminal, internal and
vinylidene double bonds, R represents an alkyl or alkenyl group
having up to 30 carbon atoms in linear, branched or cyclic form and
n is a value from 0 to 5.
43. An additive composition comprising (1) a mixture containing one
or more compounds represented by formula I and/or II; or (2) a
mixture containing at least one compound represented by formula I
and/or II and at least one compound from among the compounds
represented by formulas III to VI, wherein said formulas are:
##STR14## wherein R.sub.1 and R.sub.2 are independent of one
another and represent C.sub.3 to C.sub.30 straight or branched
alkyl, alkenyl or aryl or heteroatom derivatives thereof; R.sub.3
and R.sub.4 are independent of one another and are selected from
the group consisting of H, --OH, --OR, --COOH, --SH, --SR, straight
chain, beta branched alkyl, alkenyl radicals and hydrocarbyl groups
in oligomeric or polymeric form that are derived from propylene,
isobutylene and higher olefins having terminal, internal and
vinylidene double bonds, R represents an organic group having up to
30 carbon atoms and n is a value from 0 to 5.
44. A material resulting from the combination of an aliphatic
carboxylic acid and a polyamine.
45. The material of claim 44, wherein the material resulting from
the combination comprises a 1,2-disubstituted imidazoline.
46. The material of claim 44, wherein the molar ratio of the
carboxylic acid to the polyamine is between about 1.0 to about
2.0.
47. The material of claim 44, wherein the molar ratio of the
carboxylic acid to the polyamine is between about 1.2 to about
1.6.
48. The material of claim 44, wherein the carboxylic acid comprises
one or more of a lauric, myristic, palmitic, stearic, isostearic,
dodecenoic, hexadecenoic, oleic, iso-oleic, linoleic, arachidic
fatty acid, or combinations thereof.
49. The material of claim 44, wherein the carboxylic acid comprises
one or more of 4-dodecylbenzoic acid, 2-hexadecylnicotinic acid,
and 4-polyisobutyl acid
50. The material of claim 44, wherein the polyamine comprises a
polyethylene amine containing an internal repeating unit of
--(CH.sub.2 CH.sub.2NH).sub.x--, wherein x is an integer from about
1 to about 10.
51. The material of claim 44, wherein the polyamine comprises one
or more of a diethylene triamine, a triethylene tetramine, and a
tetraethylene pentamine.
Description
FIELD OF THE INVENTION
[0001] The present disclosure relates to fluids having improved
friction durability and .mu./v characteristics on paper, metal and
advanced friction materials. The fluids disclosed herein can
exhibit improved handling characteristics, and improved
anti-shudder durability. The invention includes devices, such as a
power transmission apparatus, lubricated with such fluids.
BACKGROUND OF THE INVENTION
[0002] New and advanced transmission systems are being developed by
the automotive industry. These new systems often involve high
energy requirements. Therefore, component protection technology
must be developed to meet the increasing energy requirements of
these advanced systems, to promote fuel economy, and to extend
satisfactory friction requirements at low and high speeds.
[0003] These new and advance transmissions used in passenger cars
and heavy duty vehicles continue to become more sophisticated in
design as vehicle technology advances. These design changes result
from the need to improve vehicle operability, reliability, and fuel
economy. Vehicle manufacturers worldwide are increasing vehicle
warranty periods and service intervals on their vehicles. This
means that the transmission and the transmission fluid must be
designed to operate reliably without maintenance for longer periods
of time. In the case of the fluid, this means longer drain
intervals. To improve vehicle operability, especially at low
temperature, manufacturers have imposed strict requirements for
fluid viscosity at -40.degree. C. To cope with longer drain
intervals and more severe operating conditions, manufacturers have
increased the requirements for fluid oxidation resistance, required
less change in viscosity with vehicle mileage (improved shear
stability), and increased the amount of wear protection that the
fluid must provide for the transmission. To improve the fuel
economy of the vehicle and reduce energy loss, manufacturers
nowadays employ continuously slipping clutches either as wet
starting clutches or as a torque converter clutch. These devices
require very precise control of fluid frictional properties.
[0004] The continuing search for methods to improve overall vehicle
fuel economy has identified the torque converter, or fluid
coupling, used between the engine and automatic transmission, as a
relatively large source of energy loss. Since the torque converter
is a fluid coupling it is not as efficient as a solid disk type
clutch. At any set of operating conditions (engine speed, throttle
position, ground speed, transmission gear ratio), there is a
relative speed difference between the driving and driven members of
the torque converter. This relative speed differential represents
lost energy which is dissipated from the torque converter as
heat.
[0005] One method of improving overall vehicle fuel economy used by
transmission builders is to build into the torque converter a
clutch mechanism capable of "locking" the torque converter.
"Locking" refers to eliminating relative motion between the driving
and driven members of the torque converter so that no energy is
lost in the fluid coupling. These "locking" or "lock-up" clutches
are very effective at capturing lost energy at high road speeds.
However, when they are used at low speeds, vehicle operation is
rough and engine vibration is transmitted through the drive train.
Rough operation and engine vibration are not acceptable to
drivers.
[0006] The higher the percentage of time that the vehicle can be
operated with the torque converter clutch engaged, the more fuel
efficient the vehicle becomes. A further generation of torque
converter clutches have been developed which operate in a
"slipping" or "continuously sliding mode." These devices have a
number of names, but are commonly referred to as continuously
slipping torque converter clutches. The difference between these
devices and lock-up clutches is that they allow some relative
motion between the driving and driven members of the torque
converter, normally a relative speed of 50 to 500 rpm. This slow
rate of slipping allows for improved vehicle performance as the
slipping clutch acts as a vibration damper. Whereas the "lock-up"
type clutch could only be used at road speeds above approximately
50 mph, the "slipping" type clutches can be used at speeds as low
as 25 mph, thereby capturing significantly more lost energy. It is
this feature that makes these devices very attractive to vehicle
manufacturers.
[0007] Another approach to reducing energy loss in the coupling
between the engine and transmission is to use a wet starting
clutch. Wet starting clutches resemble shifting clutches but are
made to handle the entire energy of the vehicle. Therefore they
tend to be physically larger than shifting clutches. However, just
as with the torque converter clutch, they are continuously slipped
to improve overall vehicle driveability and ride feel.
[0008] Continuously slipping clutches have been fitted to all types
of transmissions. Continuously slipping torque converter clutches
and/or wet starting clutches are routinely used with transmission
types such as conventional automatic transmissions, continuously
variable transmissions (CVTs), manual transmissions, and dual
clutch transmissions.
[0009] Continuously slipping clutches, such as continuously
slipping torque converter clutches, impose very exacting friction
requirements on automatic transmission fluids (ATFs) used with
them. The fluid must have a very good friction versus velocity
relationship, i.e., friction must always increase with increasing
speed. If friction decreases with increasing speed then a
self-exciting vibrational state can be set up in the driveline.
This phenomenon is commonly called "stick-slip" or "dynamic
frictional vibration" and manifests itself as "shudder" or low
speed vibration in the vehicle. Clutch shudder is very
objectionable to the driver. A fluid which allows the vehicle to
operate without vibration or shudder is said to have good
"anti-shudder" characteristics. Not only must the fluid have an
excellent friction versus velocity relationship when it is new, it
must retain those frictional characteristics over the lifetime of
the fluid, which can be the lifetime of the transmission. The
longevity of the anti-shudder performance in the vehicle is
commonly referred to as "anti-shudder durability."
[0010] Lubricating a continuously variable transmission equipped
with a steel push belt or chain drive variator and a slipping
clutch system is not a simple matter. It presents a unique
challenge of providing high steel-on-steel friction for the
variator and excellent paper-on-steel friction for the slipping
clutch. Compounding the challenge to satisfy these requirements is
the further need for the fluid to provide durability of desired
friction performance over a wide range of operating temperatures.
Therefore, the friction modifier system must provide very precise
control of the steel-on-steel friction and the paper-on-steel
friction over a wide range of operating conditions, such as a wide
range in temperatures.
[0011] Past efforts include those described in U.S. Pat. No.
5,395,539, which are said to be imidazole-free, as well as those
described in U.S. Pat. Nos. 5,750,476; 5,811,377; 5,840,662;
5,840,663; EP 0393769 B2; EP 0877784 B1; among others.
[0012] Despite these past efforts there remains a need for
compositions and methods that can address the needs in the
industry.
[0013] We have discovered certain compounds as described
hereinbelow that are readily formulated into power transmission
fluids, such as for an automatic transmission, provide a unique
solution for providing desired characteristics, such as extending
the anti-shudder durability of the fluid.
SUMMARY OF THE INVENTION
[0014] An aspect of the present invention relates to an improved
power transmitting fluid having enhanced friction durability and
.mu./v characteristics, particularly one that can exhibit a
positive .mu./v curve and can maintain high static capacity during
expected use, on paper, steel, and advanced friction materials such
as carbon fiber.
[0015] Another aspect of the present invention is to provide a
lubricant composition that carries minimal concern for skin
sensitization and related health, safety, and environmental
issues.
[0016] In an aspect of the present invention, a composition and a
method of improving the anti-shudder durability of power
transmitting fluids, particularly automatic transmission fluids,
are provided.
[0017] An embodiment of the present invention is a fluid
composition comprising a lubricating base oil, a friction modifier
produced by reacting a polyamine with an aliphatic mono acid such
as oleic or isostearic acid under conditions to form a mixture of
1,2-disubstituted imidazoline containing components, and,
optionally, other performance enhancing additives. Further
acylation of residual active nitrogens with mono or diacids or
anhydrides affords a friction modifier ("FM") compound(s) having
enhanced frictional and handling characteristics.
[0018] In one aspect of the invention, a fluid comprises a reaction
product of aliphatic carboxylic acids with polyamines, and
particularly a reaction product obtained under conditions to
produce compounds that include 1,2-disubstituted imidazolines,
including such as compounds as represented by formulas I and II
hereinbelow: ##STR1## wherein the formulae R.sub.1 can be selected
from the group consisting C.sub.3 to C.sub.30 straight chain or
branched alkyl, alkenyl, aryl, or a heteroatom derivative thereof,
or hydrocarbyl groups as oligomers/polymers derived from propylene
isobutylene and higher olefins having terminal, internal and
vinylidene double bonds, and their heteroatom derivatives; and "n"
ranges from 0 to 5; and/or such a reaction product post-treated
with a second carboxylic acid or carboxylic acid derivative.
[0019] A fluid formulated as a power transimission fluid can
contain an effective amount of at least one oil soluble ashless
dispersant, such as a succinimide dispersant, succinic ester
dispersant, succininic ester-amide dispersant, Mannich base
dispersant, phosphorylated and/or boronated forms thereof.
[0020] A fluid formulation according to an aspect of the invention
may optionally include commercially available supplemental
additives such as, for example, air expulsion additives,
antioxidants, corrosion inhibitors, foam inhibitors, metallic
detergents, organic phosphorus compounds, seal-swell agents,
viscosity index improvers, EP additives used in their conventional
amounts.
[0021] A fluid according to an aspect of the invention can be
formulated for use in an industrial gear or an automotive gear. In
an automotive aspect, a fluid can be formulated for use in a power
transmitting apparatus, such as a transmission employing one or
more of an electronically controlled converter clutch, a slipping
torque converter, a lock-up torque converter, a starting clutch,
and one or more shifting clutches; or a differential. For example,
a fluid containing a friction modifier comprised of compounds
represented by formula I and/or II, or their post-treated reaction
products, at least one ashless dispersant, and, optionally, one or
more other performance additives such as antioxidants, anti foam
agents, antiwear agents, corrosion inhibitors, EP additives,
metallic detergents, organic phosphorus compound(s), rust
inhibitors, seal-swell agents viscosity index improvers, can be
used in automatic transmissions, including those that incorporate
lock-up and dual clutches, semi-automatic transmissions, automated
manual transmissions, and continuously variable transmissions
("CVTs").
[0022] The present invention includes such further embodiments as a
method for improving the stability against oxidation degradation,
e.g. promoting the duration of a relatively constant dynamic
coefficient of friction, in a power transmission fluid by
incorporating into the fluid an effective amount of a friction
modifier compound(s) represented by a formula I to VI described
herein.
BRIEF DESCRIPTION OF THE FIGURES
[0023] FIG. 1 represents side-by-side graphs to illustrate
comparison between a conventional automatic transmission fluid A
and an automatic transmission fluid B according to this
invention.
[0024] FIG. 2 is a diagram depicting apparatus for conducting a
LFW-1 test.
DETAILED DESCRIPTION OF THE INVENTION
[0025] Vehicles meeting stringent consumer demands require
durability and performance in all of the vehicular systems. One of
the most important systems is the power transmission system
("transmission") which transmits the power generated by the
automobile engine to the wheels. It is one of the most complex
systems in the vehicle, it is also one of the most costly to
diagnose, repair, or replace. The transmission usually includes,
inter alia, a clutch with plates, a torque converter, and a
plurality of gears to alter the power delivered to the wheels by
changing the gear ratio.
[0026] Discriminating consumers primarily desire high performance,
low maintenance (high mileage between servicing), and extended life
expectancy. However, with the advent of new transmission
technologies, old standards of performance which were previously
met with approval are now becoming problematic.
[0027] The advent of electronically controlled converter clutch
(ECCC) designs, as well as vehicles equipped with a continuously
variable transmission (CVT) and advances in aerodynamic body design
generally result in passenger cars with smaller transmissions which
tend to operate with higher energy densities and higher operating
temperatures. Such changes challenge lubricant suppliers to
formulate automatic transmission fluids with new and unique
performance characteristics including higher torque and friction
durability. Original equipment manufacturers (OEMs) desire
automatic transmission fluids with frictional characteristics
capable of meeting the requirements of ECCC, CVT, and other designs
while retaining sufficient performance in the antiwear arena.
[0028] A long felt need exists for an effective way of overcoming
the problems associated with automatic transmissions, such as to
meet the needs of OEM automobile designers and suppliers, for
extended transmission fluid life and durability of high static
capacity and improved durability of the dynamic coefficient of
friction.
[0029] This invention responds to the long felt need for improved
durability in a lubricating fluid by providing an automatic
transmission fluid that exhibits good performance during its
lifetime and that can exhibit a sufficient dynamic coefficient of
friction for longer periods of time without significant
degradation, e.g. improved stability against oxidation, with
extended anti-shudder durability.
[0030] Friction modifiers can be used in automatic transmission
fluids to decrease friction between surfaces (e.g., the members of
a torque converter clutch or a shifting clutch) at low sliding
speeds. The result is a friction-vs.-velocity (.mu.-v) curve that
has a positive slope, which in turn leads to smooth clutch
engagements and minimizes "stick-slip" behavior (e.g., shudder,
noise, and harsh shifts).
[0031] Increasing desired properties, such as anti-shudder
durability and stability against oxidation with reduced variation
in the dynamic coefficient of friction, is a complex, challenging
problem. Contrary to the apparently facile solution of increasing
the amount of a conventional friction modifier in a power
transmission fluid, an increased concentration can actually reduce
the overall level of friction exhibited by the fluid. Reducing the
friction coefficients below certain minimum values is not desired
since the holding capacity of a clutch in a transmission can be
adversely reduced, thereby making clutch slippage more likely when
the transmission is being operated. Clutch wear increases and a
clutch can be ruined by unwanted slippage.
[0032] To address these and other challenges in the art, a fluid
according to the present invention contains, as an essential
component, a reaction product of an aliphatic carboxylic acid
(RCOOH) and a polyamine (PA), for example a reaction product
obtained under conditions sufficient to generate a mixture of
1,2-disubstituted imidazolines represented by formulas I and/or II,
and/or such a reaction product which is post-treated, such as with
a second carboxylic acid or a carboxylic acid derivative to obtain
compound represented by any of formulas III-VI. The composition of
the final reaction product can be determined by the molar ratio
between carboxylic acid and the polyamine.
[0033] Generalized structures I through VI exemplify typical
friction modifiers for use in the various fluid embodiments
according to the invention. These friction modifiers can form under
conditions as described below.
[0034] A reaction product of a polyamine(s) with a first acid
(R.sub.1COOH) can yield a mixture containing a compound represented
by formula I and a compound represented by formula II. A molar
excess of the first organic acid is used relative to the polyamine.
##STR2##
[0035] A molar ratio of the first carboxylic acid to the polyamine
can vary according to the desired composition of the reaction
product. In general, the molar ratio can be suitably chosen with a
range of about 1.0 to about 2.0, and as a further example, about
1.2 to about 1.6. For instance, at lower molar ratios the
composition may in principle predominately be comprised of
compound(s) represented by formula I, whereas at a higher molar
ratio the composition may in principle be predominately comprised
of compound(s) represented by formula II. The molar ratio may
correspond to an excess of the first carboxylic acid to
polyamine.
[0036] Representative first acids are those providing the R.sub.1
moieties. The R.sub.1 moieties may be independent of one another,
and can be C.sub.3 to C.sub.30 straight or branched alkyl, alkenyl
or aryl groups or a heteroatom derivative thereof, such as an alkyl
having heteroatoms, as one example. The present invention therefore
contemplates, in one of its embodiments, using a combination of
first acids. Representative moieties include fatty acids such as
lauric, myristic, palmitic, stearic, isostearic, dodecenoic,
hexadecenoic, oleic, iso-oleic, linoleic, arachidic, or a
combination of any thereof. The R.sub.1 group may incorporate
hydrocarbyl aromatic acids like 4-dodecylbenzoic acid,
2-hexadecylnicotinic acid, and 4-polyisobutyl acid. Suitable
friction modifiers include those that are obtained from the
reaction of fatty acids exemplified by oleic acid or isostearic
acid with a polyamine, such as triethylene tetramine.
[0037] Heteroatom derivatives of R.sub.1 can include O, S, N,
and/or P atoms as would be understood by those skilled in the
art.
[0038] Representative polyamines can be linear, as connoted by the
compounds represented by formulas I to VI (n=0 to 5), or branched.
An exemplary class of polyethylene amines contains an internal
repeating unit of --(CH.sub.2 CH.sub.2NH).sub.x-- where x can be an
integer from 1 to 10, and as a further example, x can be an integer
of 1 to 6. In the case where the polyamine is represented by a
formula H.sub.2N--(CH.sub.2 CH.sub.2NH).sub.x--CH.sub.2
CH.sub.2NH.sub.2, and x is 1 it is diethylene triamine, when x is 2
it is triethylene tetramine, and when x is 3 it is tetraethylene
pentamine, which are among the suitable polyamines. Commercial
mixtures of higher polyamines are also suitable. Amino groups can
be attached to or be part of an aromatic or aliphatic ring
structure, such as o-phenylenediamine, p-phenylenediamine,
4,4'-diaminodiphenylamine, melamine, or 1,8-diamino-p-mentane,
among others.
[0039] For instance, reacting a selected first acid, such as
C.sub.17H.sub.33COOH, and a suitable selected polyamine, such as
where x=2, in a molar ratio of about 4 to about 3 at a suitable
elevated temperature in a range of about 120.degree. C. to about
180.degree. C., such as about 150.degree. C., for a sufficient
period of time, such as for about 5 to about 20 hours or, as a
further example, for about 12 to about 16 hours, can produce a
reaction product containing compound(s) represented by the formulas
I and II wherein R.sub.1 is a C.sub.17H.sub.35 moiety. The relative
ratio of the compound represented by the just described formula I
to the compound represented by the just described formula II can,
in principle, be about 2:1. Other ratios may be feasible. The
relative ratio of a compound(s) represented by formula I to a
compound(s) represented by formula II can be determined by the
ratio of carboxylic acid to polyamine.
[0040] An embodiment of the invention is a fluid, such as a power
transmission fluid or a concentrate, which contains at least one
compound represented by formula I and/or formula II.
[0041] A post-treatment of a mixture (or reaction product)
containing compound(s) represented by formulas I and/or II with at
least one second organic acid (R.sub.2COOH) can be conducted. The
second organic acid may be in an amount sufficient to acylate all
reactive nitrogen atoms to obtain a second mixture (or second
reaction product) containing a compound(s) represented by formula
II and a compound(s) represented by formula IV: ##STR3## The level
of acylation may, in general, be above about 0% to about 100%, and
a further exemplary range can be, for instance, from about 50% to
about 100%.
[0042] Representative second acids are those providing the R.sub.2
moieties. The R.sub.2 moieties may be independent of one another,
and can be C.sub.3 to C.sub.30 straight or branched alkyl, alkenyl,
or aryl, or heteroatom derivatives thereof, such as an alkyl having
heteroatoms, as one example. The present invention therefore also
contemplates using a combination of first acids. Representative
moieties include those from fatty acids such as lauric, myristic,
palmytic, stearic, iso-stearic, dodecenoic, hexadecenoic, oleic,
iso-oleic, linoleic, arachidic, or a mixture of any thereof. The
R.sub.2 group may incorporate hydrocarbyl aromatic or
heteroaromatic acids, such as 4-dodecylbenzoic acid,
2-hexadecylnicotinic acid, or 4-polyisobutyl benzoic acid, among
others.
[0043] Heteroatom derivatives of R.sub.2 can include O, S, N,
and/or P atoms as would be understood by those skilled in the
art.
[0044] An embodiment of the invention is a fluid, such as a power
transmission fluid or a concentrate, which contains one or more
compounds represented by structures III and IV.
[0045] A post-treatment of a mixture containing compounds
represented by formulas I and II with an excess of substituted
anhydride, such as a substituted succinic acid or anhydride, can be
conducted. The amount of the substituted organic acid or anhydride
may be in an amount sufficient to acylate all or a portion of the
reactive nitrogens to yield a mixture of compounds that includes a
compound(s) represented by formula V and a compound(s) represented
by formula VI: ##STR4## The level of acylation may, in general, be
above about 0% to about 100%, and a further exemplary range can be,
for instance, from about 50% to about 100%.
[0046] Representative of the substituted organic acids and
anhydrides are those corresponding to the R.sub.3 and R.sub.4
moieties. The R.sub.3 and R.sub.4 moieties may be independent of
each other, and may reflect the use of combinations of suitable
reagents. The R.sub.3 and R.sub.4 groups can be selected from a
group consisting of H, --OH, --OR, --COOH, --SH, --SR, straight
chain, branched alkyl, alkenyl radicals or hydrocarbyl groups in
oligomeric or polymeric forms of propylene, isobutylene and higher
olefins having terminal, internal, and vinylidene double bonds. The
molecular weight of R.sub.3 and R.sub.4 can vary and may be as high
as 1000 amu. The R represents an alkyl or alkenyl group having up
to 30 carbon atoms in linear, branched or cyclic form, for example
from 16 to 22 carbon atoms.
[0047] Accordingly, representative substituted organic acids and
anhydrides include low molecular weight, oil-insoluble acids or
anhydrides. Examples include succinic anhydride, phthalic
anhydride, tartaric acid, citric acid, maleic acid, and
mercaptosuccinic acid.
[0048] A suitable post-treatment reagent is a succinic anhydride
produced from isomerization of linear .alpha.-olefins with an acid
catalyst followed by reaction with maleic anhydride. Such
preparation is described, for example, in U.S. Pat. Nos. 6,548,458;
5,620,486; 5,393,309; 5,021,169; 4,958,034; 4,234,435; 3,676,089;
3,361,673; and 3,172,892 and European Patent 0623631 B1, herein
incorporated by reference.
[0049] An embodiment of the invention is a fluid, such as a power
transmission fluid or a concentrate, which contains one or more
compound(s) represented by formula V and/or VI.
[0050] The friction modifier(s) described above are idealized
compositions in the sense that they don't incorporate cross-linking
products and by-products due to variation in the level of
acylation.
[0051] A fluid according to the invention can contain one or more
compounds from among those represented by formulas I to VI,
including any combination of such compounds. Suitable mixtures of
compounds include, for instance, a mixture of compounds represented
by formula I, a mixture of compounds represented by formula II, a
mixture of compounds represented by formula III, a mixture of
compounds represented by formula IV, a mixture of compounds
represented by formula V, a mixture of compounds represented by
formula VI, a mixture of a compound(s) represented by formula I and
a compound(s) represented by formula II, a mixture of a compound(s)
represented by formula III and a compound(s) represented by formula
IV, a mixture of a compound(s) represented by formula V and a
compound(s) represented by formula VI, a mixture of compounds from
among those represented by formulas I, II, III, and IV, a mixture
of compounds from among those represented by formula I, II, V and
VI.
[0052] A combination of the suitable reactants and reagents can be
selected to produce a friction modifier composition that contains a
compound(s) where R.sub.1 is oleyl or isostearyl, and R.sub.3
and/or R.sub.4 is an isomerized .alpha.-olefin derived hydrocarbyl
group. Further, R.sub.3 and/or R.sub.4 may comprise a moiety from
polyisobutylene having a molecular weight of about 200 to about 950
amu or a C.sub.16 to C.sub.22 isomerized .alpha.-olefin.
[0053] Compounds represented by formulas I to VI can each be
borated, maleated, treated with an inorganic acid, such as
phosphoric, phosphorous and sulfuric acids, as described in U.S.
Pat. Nos. 3,254,025; 3,502,677; 4,686,054; and 4,857,214.
[0054] The level of this component in a finished oil-containing
power transmission fluid may range from about 0.01 to about 10%
(weight percent). A suitable range is from about 0.1 to about 5.0%
weight percent. For example, the component can comprise a mixture
of compounds represented by formula V and by formula VI.
Dispersants (Oil-Soluble)
[0055] In an aspect of the invention, the fluid can contain at
least one oil soluble type dispersant, such as a succinimide
dispersant, succinic ester dispersant, succininic ester-amide
dispersant, Mannich base dispersant, phosphorylated and/or
boronated forms thereof. The total dispersant content of a fluid,
such as a power transimission fluid, according to the invention can
vary from 0.1 to 20 weight percent. As a further example, the
suitable range can be from about 2.0 to about 7.0 weight
percent.
[0056] Oil-soluble dispersants may include ashless dispersants such
as succinimide dispersants, Mannich base dispersants, and polymeric
polyamine dispersants. Hydrocarbyl-substituted succinic acylating
agents are used to make hydrocarbyl-substituted succinimides. The
hydrocarbyl-substituted succinic acylating agents include, but are
not limited to, hydrocarbyl-substituted succinic acids,
hydrocarbyl-substituted succinic anhydrides, the
hydrocarbyl-substituted succinic acid halides (especially the acid
fluorides and acid chlorides), and the esters of the
hydrocarbyl-substituted succinic acids and lower alcohols (e.g.,
those containing up to 7 carbon atoms), that is,
hydrocarbyl-substituted compounds which can function as carboxylic
acylating agents.
[0057] Hydrocarbyl substituted acylating agents are made by
reacting a polyolefin or chlorinated polyolefin of appropriate
molecular weight with maleic anhydride. Similar carboxylic
reactants can be used to make the acylating agents. Such reactants
may include, but are not limited to, maleic acid, fumaric acid,
malic acid, tartaric acid, itaconic acid, itaconic anhydride,
citraconic acid, citraconic anhydride, mesaconic acid, ethylmaleic
anhydride, dimethylmaleic anhydride, ethylmaleic acid,
dimethylmaleic acid, hexylmaleic acid, and the like, including the
corresponding acid halides and lower aliphatic esters.
[0058] The molecular weight of the olefin can vary depending upon
the intended use of the substituted succinic anhydrides. Typically,
the substituted succinic anhydrides will have a hydrocarbyl group
of from about 8 to about 500 carbon atoms. However, substituted
succinic anhydrides used to make lubricating oil dispersants will
typically have a hydrocarbyl group of about 40 to about 500 carbon
atoms. With high molecular weight substituted succinic anhydrides,
it is more accurate to refer to number average molecular weight
(Mn) since the olefins used to make these substituted succinic
anhydrides may include a mixture of different molecular weight
components resulting from the polymerization of low molecular
weight olefin monomers such as ethylene, propylene, and
isobutylene.
[0059] The mole ratio of maleic anhydride to olefin can vary
widely. It may vary, for example, from about 5:1 to about 1:5, or
for example, from about 1:1 to about 3:1. With olefins such as
polyisobutylene having a number average molecular weight of about
500 to about 7000, or as a further example, about 800 to about 3000
or higher and the ethylene-alpha-olefin copolymers, the maleic
anhydride may be used in stoichiometric excess, e.g. about 1.1 to
about 3 moles maleic anhydride per mole of olefin. The unreacted
maleic anhydride can be vaporized from the resultant reaction
mixture.
[0060] Polyalkenyl succinic anhydrides may be converted to
polyalkyl succinic anhydrides by using conventional reducing
conditions such as catalytic hydrogenation. For catalytic
hydrogenation, a suitable catalyst is palladium on carbon.
Likewise, polyalkenyl succinimides may be converted to polyalkyl
succinimides using similar reducing conditions.
[0061] The polyalkyl or polyalkenyl substituent on the succinic
anhydrides employed herein is generally derived from polyolefins,
which are polymers or copolymers of mono-olefins, particularly
1-mono-olefins, such as ethylene, propylene, and butylene. The
mono-olefin employed may have about 2 to about 24 carbon atoms, or
as a further example, about 3 to about 12 carbon atoms. Other
suitable mono-olefins include propylene, butylene, particularly
isobutylene, 1-octene, and 1-decene. Polyolefins prepared from such
mono-olefins include polypropylene, polybutene, polyisobutene, and
the polyalphaolefins produced from 1-octene and 1-decene.
[0062] In some embodiments, the ashless dispersant may include one
or more alkenyl succinimides of an amine having at least one
primary amino group capable of forming an imide group. The alkenyl
succinimides may be formed by conventional methods such as by
heating an alkenyl succinic anhydride, acid, acid-ester, acid
halide, or lower alkyl ester with an amine containing at least one
primary amino group. The alkenyl succinic anhydride may be made
readily by heating a mixture of polyolefin and maleic anhydride to
about 180.degree. C.-220.degree. C. The polyolefin may be a polymer
or copolymer of a lower mono-olefin such as ethylene, propylene,
isobutene, and the like, having a number average molecular weight
in the range of about 300 to about 3000 as determined by gel
permeation chromatography (GPC).
[0063] Amines which may be employed in forming the ashless
dispersant include any that have at least one primary amino group
which can react to form an imide group and at least one additional
primary or secondary amino group and/or at least one hydroxyl
group. Representative examples include: N-methyl-propanediamine,
N-dodecylpropanediamine, N-aminopropyl-piperazine, ethanolamine,
N-ethanol-ethylenediamine, and the like.
[0064] Suitable amines may include alkylene polyamines, such as
propylene diamine, dipropylene triamine, di-(1,2-butylene)triamine,
and tetra-(1,2-propylene)pentamine. A further example includes the
ethylene polyamines which can be depicted by the formula
H.sub.2N(CH.sub.2CH.sub.2NH).sub.nH, wherein n may be an integer
from about 1 to about 10. These include: ethylene diamine,
diethylene triamine (DETA), triethylene tetramine (TETA),
tetraethylene pentamine (TEPA), pentaethylene hexamine (PEHA), and
the like, including mixtures thereof in which case n is the average
value of the mixture. Such ethylene polyamines have a primary amine
group at each end so they may form mono-alkenylsuccinimides and
bis-alkenylsuccinimides. Commercially available ethylene polyamine
mixtures may contain minor amounts of branched species and cyclic
species such as N-aminoethyl piperazine,
N,N'-bis(aminoethyl)piperazine, N,N'-bis(piperazinyl)ethane, and
like compounds. The commercial mixtures may have approximate
overall compositions falling in the range corresponding to
diethylene triamine to tetraethylene pentamine. The molar ratio of
polyalkenyl succinic anhydride to polyalkylene polyamines may be
from about 1:1 to about 3.0:1.
[0065] In some embodiments, the ashless dispersant may include the
products of the reaction of a polyethylene polyamine, e.g.,
triethylene tetramine or tetraethylene pentamine, with a
hydrocarbon substituted carboxylic acid or anhydride made by
reaction of a polyolefin, such as polyisobutene, of suitable
molecular weight, with an unsaturated polycarboxylic acid or
anhydride, e.g., maleic anhydride, maleic acid, fumaric acid, or
the like, including mixtures of two or more such substances.
[0066] Polyamines that are also suitable in preparing the
dispersants described herein include N-arylphenylenediamines, such
as N-phenylphenylenediamines, for example,
N-phenyl-1,4-phenylenediamine, N-phenyl-1,3-phenylenediamine, and
N-phenyl-1,2-phenylenediamine; aminothiazoles such as
aminothiazole, aminobenzothiazole, aminobenzothiadiazole, and
aminoalkylthiazole; aminocarbazoles; aminoindoles; aminopyrroles;
amino-indazolinones; aminomercaptotriazoles; aminoperimidines;
aminoalkyl imidazoles, such as 1-(2-aminoethyl) imidazole,
1-(3-aminopropyl) imidazole; and aminoalkyl morpholines, such as
4-(3-aminopropyl) morpholine. These polyamines are described in
more detail in U.S. Pat. Nos. 4,863,623 and 5,075,383. Such
polyamines can provide additional benefits, such as anti-wear and
antioxidancy, to the final products.
[0067] Additional polyamines useful in forming the
hydrocarbyl-substituted succinimides include polyamines having at
least one primary or secondary amino group and at least one
tertiary amino group in the molecule as taught in U.S. Pat. Nos.
5,634,951 and 5,725,612. Examples of suitable polyamines include
N,N,N'',N''-tetraalkyldialkylenetriamines (two terminal tertiary
amino groups and one central secondary amino group),
N,N,N',N''-tetraalkyltrialkylenetetramines (one terminal tertiary
amino group, two internal tertiary amino groups and one terminal
primary amino group),
N,N,N',N'',N'''-pentaalkyltrialkylenetetramines (one terminal
tertiary amino group, two internal tertiary amino groups and one
terminal secondary amino group),
tris(dialkylaminoalkyl)-aminoalkylmethanes (three terminal tertiary
amino groups and one terminal primary amino group), and like
compounds, wherein the alkyl groups are the same or different and
typically contain no more than about 12 carbon atoms each, and
which may contain from about 1 to about 4 carbon atoms each. As a
further example, these alkyl groups may be methyl and/or ethyl
groups. Polyamine reactants of this type may include
dimethylaminopropylamine (DMAPA) and N-methyl piperazine.
[0068] Hydroxyamines suitable for use herein include compounds,
oligomers or polymers containing at least one primary or secondary
amine capable of reacting with the hydrocarbyl-substituted succinic
acid or anhydride. Examples of hydroxyamines suitable for use
herein include aminoethylethanolamine (AEEA),
aminopropyldiethanolamine (APDEA), ethanolamine, diethanolamine
(DEA), partially propoxylated hexamethylene diamine (for example
HMDA-2PO or HMDA-3PO), 3-amino-1,2-propanediol,
tris(hydroxymethyl)aminomethane, and 2-amino-1,3-propanediol.
[0069] The mole ratio of amine to hydrocarbyl-substituted succinic
acid or anhydride may range from about 1:1 to about 3.0:1. Another
example of a mole ratio of amine to hydrocarbyl-substituted
succinic acid or anhydride may range from about 1.5:1 to about
2.0:1.
[0070] The foregoing dispersant may also be a post-treated
dispersant made, for example, by treating the dispersant with
maleic anhydride and boric acid as described, for example, in U.S.
Pat. No. 5,789,353, or by treating the dispersant with nonylphenol,
formaldehyde and glycolic acid as described, for example, in U.S.
Pat. No. 5,137,980.
[0071] The Mannich base dispersants may be a reaction product of an
alkyl phenol, typically having a long chain alkyl substituent on
the ring, with one or more aliphatic aldehydes containing from
about 1 to about 7 carbon atoms (especially formaldehyde and
derivatives thereof), and polyamines (especially polyalkylene
polyamines). For example, a Mannich base ashless dispersants may be
formed by condensing about one molar proportion of long chain
hydrocarbon-substituted phenol with from about 1 to about 2.5 moles
of formaldehyde and from about 0.5 to about 2 moles of polyalkylene
polyamine.
[0072] Hydrocarbon sources for preparation of the Mannich polyamine
dispersants may be those derived from substantially saturated
petroleum fractions and olefin polymers, such as polymers of
mono-olefins having from about 2 to about 6 carbon atoms. The
hydrocarbon source generally contains, for example, at least about
40 carbon atoms, and as a further example, at least about 50 carbon
atoms to provide substantial oil solubility to the dispersant. The
olefin polymers having a GPC number average molecular weight
between about 600 and about 5,000 are suitable for reasons of easy
reactivity and low cost. However, polymers of higher molecular
weight can also be used. Especially suitable hydrocarbon sources
are isobutylene polymers and polymers made from a mixture of
isobutene and a raffinate I stream.
[0073] Suitable Mannich base dispersants may be Mannich base
ashless dispersants formed by condensing about one molar proportion
of long chain hydrocarbon-substituted phenol with from about 1 to
about 2.5 moles of formaldehyde and from about 0.5 to about 2 moles
of polyalkylene polyamine.
[0074] Polymeric polyamine dispersants suitable as the ashless
dispersants are polymers containing basic amine groups and oil
solubilizing groups (for example, pendant alkyl groups having at
least about 8 carbon atoms). Such materials are illustrated by
interpolymers formed from various monomers such as decyl
methacrylate, vinyl decyl ether or relatively high molecular weight
olefins, with aminoalkyl acrylates and aminoalkyl acrylamides.
Examples of polymeric polyamine dispersants are set forth in U.S.
Pat. Nos. 3,329,658; 3,449,250; 3,493,520; 3,519,565; 3,666,730;
3,687,849; and 3,702,300. Polymeric polyamines may include
hydrocarbyl polyamines wherein the hydrocarbyl group is composed of
the polymerization product of isobutene and a raffinate I stream as
described above. PIB-amines and PIB-polyamines may also be
used.
[0075] Methods for the production of ashless dispersants as
described above are known to those skilled in the art and are
reported in the patent literature. For example, the synthesis of
various ashless dispersants of the foregoing types is described in
such patents as U.S. Pat. Nos. 2,459,112; 2,962,442, 2,984,550;
3,036,003; 3,163,603; 3,166,516; 3,172,892; 3,184,474; 3,202,678;
3,215,707; 3,216,936; 3,219,666; 3,236,770; 3,254,025; 3,271,310;
3,272,746; 3,275,554; 3,281,357; 3,306,908; 3,311,558; 3,316,177;
3,331,776; 3,340,281; 3,341,542; 3,346,493; 3,351,552; 3,355,270;
3,368,972; 3,381,022; 3,399,141; 3,413,347; 3,415,750; 3,433,744;
3,438,757; 3,442,808; 3,444,170; 3,448,047; 3,448,048; 3,448,049;
3,451,933; 3,454,497; 3,454,555; 3,454,607; 3,459,661; 3,461,172;
3,467,668; 3,493,520; 3,501,405; 3,522,179; 3,539,633; 3,541,012;
3,542,680; 3,543,678; 3,558,743; 3,565,804; 3,567,637; 3,574,101;
3,576,743; 3,586,629; 3,591,598; 3,600,372; 3,630,904; 3,632,510;
3,632,511; 3,634,515; 3,649,229; 3,697,428; 3,697,574; 3,703,536;
3,704,308; 3,725,277; 3,725,441; 3,725,480; 3,726,882; 3,736,357;
3,751,365; 3,756,953; 3,793,202; 3,798,165; 3,798,247; 3,803,039;
3,804,763; 3,836,471; 3,862,981; 3,872,019; 3,904,595; 3,936,480;
3,948,800; 3,950,341; 3,957,746; 3,957,854; 3,957,855; 3,980,569;
3,985,802; 3,991,098; 4,006,089; 4,011,380; 4,025,451; 4,058,468;
4,071,548; 4,083,699; 4,090,854; 4,173,540; 4,234,435; 4,354,950;
4,485,023; 5,137,980; and Re 26,433, herein incorporated by
reference.
[0076] An example of a suitable ashless dispersant is a borated
dispersant. Borated dispersants may be formed by boronating
(borating) an ashless dispersant having basic nitrogen and/or at
least one hydroxyl group in the molecule, such as a succinimide
dispersant, succinamide dispersant, succinic ester dispersant,
succinic ester-amide dispersant, Mannich base dispersant, or
hydrocarbyl amine or polyamine dispersant. Methods that can be used
for boronating the various types of ashless dispersants described
above are described in U.S. Pat. Nos. 3,087,936; 3,254,025;
3,281,428; 3,282,955; 2,284,409; 2,284,410; 3,338,832; 3,344,069;
3,533,945; 3,658,836; 3,703,536; 3,718,663; 4,455,243; and
4,652,387.
[0077] The borated dispersant may include a high molecular weight
dispersant treated with boron such that the borated dispersant
includes up to about 2 wt. % of boron. As another example the
borated dispersant may include from about 0.8 wt. % or less of
boron. As a further example, the borated dispersant may include
from about 0.1 to about 0.7 wt. % of boron. As another example, the
borated dispersant may include from about 0.25 to about 0.7 wt. %
of boron. As a still further example, the borated dispersant may
include from about 0.35 to about 0.7 wt. % of boron. The dispersant
may be dissolved in oil of suitable viscosity for ease of handling.
It should be understood that the weight percentages given here are
for neat dispersant, without any diluent oil added.
[0078] A dispersant may be further reacted with an organic acid, an
anhydride, and/or an aldehyde/phenol mixture. Such a process may
enhance compatibility with elastomer seals, for example. The
borated dispersant may further include a mixture of borated
dispersants. As a further example, the borated dispersant may
include a nitrogen-containing dispersant and/or may be free of
phosphorus.
Other Additives
[0079] The power transmission fluid may also include conventional
additives of the type used in automatic transmission fluid
formulations and gear lubricants. Such additives include, but are
not limited to antifoamants (foam inhibitors), antioxidants,
anti-rust additives, antiwear additives, colorants, corrosion
inhibitors, dispersants, metal deactivators, metallic detergents,
organic phosphorus compounds, pour point depressants, seal swell
agents, and/viscosity index improvers. Additives are generally
described in C. V. Smalheer et al., Lubricant Additives, pages 1-11
(1967) and in U.S. Pat. No. 4,105,571, among others. The
supplemental additives include those that are commercially
available.
Antifoam Agents
[0080] In some embodiments, a fluid according to the present
invention can include a foam inhibitor(s), which is another
component suitable for use in the compositions. Foam inhibitors may
be selected from silicones, polyacrylates, surfactants, and the
like. The amount of antifoam agent in the transmission fluid
formulations described herein may range from about 0.001 wt. % to
about 0.5 wt. % based on the total weight of the formulation. As a
further example, antifoam agent may be present in an amount from
about 0.01 wt. % to about 0.1 wt. %.
Antioxidant Additives
[0081] In some embodiments, antioxidant compounds may be included
in the compositions. Antioxidants include phenolic antioxidants,
aromatic amine antioxidants, sulfurized phenolic antioxidants, and
organic phosphites, among others. Examples of phenolic antioxidants
include 2,6-di-tert-butylphenol, liquid mixtures of tertiary
butylated phenols, 2,6-di-tert-butyl-4-methylphenol,
4,4'-methylenebis(2,6-di-tert-butylphenol),2,2'-methylenebis(4-methyl6-te-
rt-butylphenol), mixed methylene-bridged polyalkyl phenols, and
4,4'-thiobis(2-methyl-6-tert-butylphenol),
N,N'-di-sec-butyl-phenylenediamine, 4-isopropylaminodiphenylamine,
phenyl-.alpha.-naphthyl amine, phenyl-.alpha.-naphthyl amine,
diarylamines such as diphenylamine and ring-alkylated diarylamines
such as ring-alkylated diphenylamines. Examples include the
sterically hindered tertiary butylated phenols, bisphenols and
cinnamic acid derivatives and combinations thereof. The amount of
antioxidant in the transmission fluid compositions described herein
may range from about 0.01 to about 10 wt. % based on the total
weight of the fluid formulation. As a further example, antioxidant
may be present in an amount from about 0.1 wt. % to about 2.0 wt.
%.
Anti-Rust Additives
[0082] A fluid composition according to the present invention may
include one or more rust or corrosion inhibitors. Such materials
include monocarboxylic acids and polycarboxylic acids. Examples of
suitable monocarboxylic acids are octanoic acid, decanoic acid and
dodecanoic acid. Suitable polycarboxylic acids include dimer and
trimer acids such as are produced from such acids as tall oil fatty
acids, oleic acid, linoleic acid, or the like. Another useful type
of rust inhibitor may comprise alkenyl succinic acid and alkenyl
succinic anhydride corrosion inhibitors such as, for example,
tetrapropenylsuccinic acid, tetrapropenylsuccinic anhydride,
tetradecenylsuccinic acid, tetradecenylsuccinic anhydride,
hexadecenylsuccinic acid, hexadecenylsuccinic anhydride, and the
like. Also useful are the half esters of alkenyl succinic acids
having about 8 to about 24 carbon atoms in the alkenyl group with
alcohols such as the polyglycols. Other suitable rust or corrosion
inhibitors include ether amines; acid phosphates; amines;
polyethoxylated compounds such as ethoxylated amines, ethoxylated
phenols, and ethoxylated alcohols; imidazolines; aminosuccinic
acids or derivatives thereof, and the like. Materials of these
types are commercially available. Mixtures of such rust or
corrosion inhibitors can be used. The amount of rust inhibitor in
the transmission fluid formulations described herein may range from
about 0.01 to about 5.0 wt. % based on the total weight of the
formulation.
Antiwear Additives
[0083] The antiwear characteristics of a finished fluid optionally
may be modified by addition of one or more supplemental antiwear
agents. The supplemental antiwear agents may include
phosphorus-containing antiwear agents, such as those comprising an
organic ester of phosphoric acid, phosphorous acid, or an amine
salt thereof. For example, the phosphorus-containing antiwear agent
may include one or more of a dihydrocarbyl phosphite, a
trihydrocarbyl phosphite, a dihydrocarbyl phosphate, a
trihydrocarbyl phosphate, any sulfur analogs thereof, and any amine
salts thereof. As a further example, the phosphorus-containing
antiwear agent may include at least one of dibutyl hydrogen
phosphite and an amine salt of sulfurized dibutyl hydrogen
phosphite.
[0084] The phosphorus-containing antiwear agent may be present in
an amount sufficient to provide about 50 to about 500 parts per
million by weight of phosphorus in the power transmission fluid. As
a further example, the phosphorus-containing antiwear agent may be
present in an amount sufficient to provide about 150 to about 300
parts per million by weight of phosphorus in the power transmission
fluid.
[0085] The power transmission fluid may include from about 0.01 wt.
% to about 5.0 wt. % of the phosphorus-containing antiwear agent.
As a further example, the power transmission fluid may include from
about 0.2 wt. % to about 0.3 wt. % of the phosphorus-containing
antiwear agent. As an example, the power transmission fluid may
include from about 0.1 wt. % to about 0.2 wt. % of a dibutyl
hydrogen phosphite or 0.3 wt. % to about 0.4 wt. % an amine salt of
a sulfurized dibutyl hydrogen phosphate.
Colorant (Dye)
[0086] In some embodiments, a fluid according to the present
invention can include a colorant to give the fluid a detectable
character. Generally, azo class dyes are used, such as C.I. Solvent
Red 24 or C.I. Solvent Red 164, as set forth in the "Color Index"
of the American Association of textile Chemists and Colorists and
the Society of Dyers and Colourists (U.K.). For automatic
transmission fluids, Automatic Red Dye is preferred. Dye is present
in a very minimal amount, such as about 200 to about 300 ppm in the
finished fluid.
Corrosion Inhibitors
[0087] In some embodiments, a fluid according to the present
invention can include copper corrosion inhibitors. Suitable copper
corrosion inhibitors include such compounds as thiazoles,
triazoles, and thiadiazoles. Examples of such compounds include
benzotriazole, tolyltriazole, octyltriazole, decyltriazole,
dodecyltriazole, 2-mercapto benzothiazole,
2,5-dimercapto-1,3,4-thiadiazole,
2-mercapto-5-hydrocarbylthio-1,3,4-thiadiazoles,
2-mercapto-5-hydrocarbyldithio-1,3,4-thiadiazoles,
2,5-bis(hydrocarbylthio)-1,3,4-thiadiazoles, and
2,5-bis(hydrocarbyldithio)-1,3,4-thiadiazoles. Suitable compounds
include the 1,3,4-thiadiazoles, a number of which are available as
articles of commerce, and also combinations of triazoles such as
tolyltriazole with a 1,3,5-thiadiazole such as a
2,5-bis(alkyldithio)-1,3,4-thiadiazole. Regarding dialkyl
thiadiazoles, for imparting corrosion inhibition, that additive
previously has been used in much smaller treat levels than the
levels used in the present invention to enhance extreme pressure
and antiwear properties (when used in combination with relatively
high levels of sulfurized fatty oil as indicated herein). The
1,3,4-thiadiazoles are generally synthesized from hydrazine and
carbon disulfide by known procedures. See, for example, U.S. Pat.
Nos. 2,765,289; 2,749,311; 2,760,933; 2,850,453; 2,910,439;
3,663,561; 3,862,798; and 3,840,549.
Other Friction Modifiers
[0088] A fluid according to the present invention containing a
friction modifier compound represented by a formula I-VI
hereinabove, or any combination of such friction modifiers, may
optionally be contain other friction modifiers, including those
known in the art. Exemplary of such other friction modifiers are
alkylated or ethoxylated fatty amines, amides glycerol esters and
different imidazolines (or their derivatives).
[0089] Other friction modifiers include such compounds as aliphatic
amines or ethoxylated aliphatic amines, ether amines, alkoxylated
ether amines, aliphatic fatty acid amides, acylated amines,
aliphatic carboxylic acids, aliphatic carboxylic esters, polyol
esters, aliphatic carboxylic ester-amides, imidazolines, tertiary
amines, aliphatic phosphonates, aliphatic phosphates, aliphatic
thiophosphonates, aliphatic thiophosphates, etc., wherein the
aliphatic group usually contains one or more carbon atoms so as to
render the compound suitably oil soluble. As a further example, the
aliphatic group may contain about 8 or more carbon atoms. Also
suitable are aliphatic substituted succinimides formed by reacting
one or more aliphatic succinic acids or anhydrides with ammonia or
primary amines.
[0090] The succinimide may include the reaction product of a
succinic anhydride and ammonia or primary amine. The alkenyl group
of the alkenyl succinic acid may be a short chain alkenyl group,
for example, the alkenyl group may include from about 12 to about
36 carbon atoms. Further, the succinimide may include an about
C.sub.12 to about C.sub.36 aliphatic hydrocarbyl succinimide. As a
further example, the succinimide may include an about C.sub.16 to
about C.sub.28 aliphatic hydrocarbyl succinimide. As an even
further example, the succinimide may include an about C.sub.18 to
about C.sub.24 aliphatic hydrocarbyl succinimide.
[0091] The succinimide may be prepared from a succinic anhydride
and ammonia as described in European Patent Application No. 0 020
037, herein incorporated by reference. In some embodiments, the
succinimide may include one or more of a compound(s) having the
following structure: ##STR5## [0092] wherein Z may have the
structure: ##STR6## wherein either R.sup.1 or R.sup.2 may be
hydrogen, but not both, and wherein R.sup.1 and R.sup.2 may be
independently straight or branched chain hydrocarbon groups
containing from about 1 to about 34 carbon atoms such that the
total number of carbon atoms in R.sup.1 and R.sup.2 is from about
11 to about 35; X is an amino group derived from ammonia or a
primary amine; and wherein, in addition to or in the alternative,
the parent succinic anhydride may be formed by reacting maleic
acid, anhydride, or ester with an internal olefin containing about
12 to about 36 carbon atoms, said internal olefin being formed by
isomerizing the olefinic double bond of a linear .alpha.-olefin or
mixture thereof to obtain a mixture of internal olefins. The
reaction may involve an equimolar amount of ammonia and may be
carried out at elevated temperatures with the removal of water.
[0093] One group of other friction modifiers includes the
N-aliphatic hydrocarbyl-substituted diethanol amines in which the
N-aliphatic hydrocarbyl-substituent is at least one straight chain
aliphatic hydrocarbyl group free of acetylenic unsaturation and
having in the range of about 14 to about 20 carbon atoms.
[0094] An example of a suitable other friction modifier system is
composed of a combination of at least one N-aliphatic
hydrocarbyl-substituted diethanol amine and at least one
N-aliphatic hydrocarbyl-substituted trimethylene diamine in which
the N-aliphatic hydrocarbyl-substituent is at least one straight
chain aliphatic hydrocarbyl group free of acetylenic unsaturation
and having in the range of about 14 to about 20 carbon atoms.
Further details concerning this friction modifier system are set
forth in U.S. Pat. Nos. 5,372,735 and 5,441,656.
[0095] Another example of a suitable other friction modifier system
is one based on the combination of (i) at least one
di(hydroxyalkyl) aliphatic tertiary amine in which the hydroxyalkyl
groups, being the same or different, each contain from about 2 to
about 4 carbon atoms, and in which the aliphatic group is an
acyclic hydrocarbyl group containing from about 10 to about 25
carbon atoms, and (ii) at least one hydroxyalkyl aliphatic
imidazoline in which the hydroxyalkyl group contains from about 2
to about 4 carbon atoms, and in which the aliphatic group is an
acyclic hydrocarbyl group containing from about 10 to about 25
carbon atoms. For further details concerning this friction modifier
system, reference should be had to U.S. Pat. No. 5,344,579.
[0096] Another suitable group of other friction modifiers includes
polyolesters, for example, glycerol monooleate (GMO), glycerol
monolaurate (GML), and the like.
[0097] Other friction modifiers include, for instance, those
described in European Patent Publications 877784B1, 856042, and
988357; U.S. Pat. Nos. 5,750,476 and 5,942,472; and PCT patent
publication WO 97/14772 (Apr. 24, 1997), among others.
[0098] In general, in a composition embodiment, the composition,
such as a power transmission fluid or an additive package, may
contain up to about 5 wt. %, or, as a further example, from about
0.01 to about 3 wt. % of one or more of these other, additional,
friction modifiers.
Metallic Detergents
[0099] Certain metallic detergents may optionally be included in an
additive package or in a power transmission fluid of the present
invention. A suitable metallic detergent may include an oil-soluble
neutral or overbased salt of alkali or alkaline earth metal with
one or more of the following acidic substances (or mixtures
thereof): (1) a sulfonic acid, (2) a carboxylic acid, (3) a
salicylic acid, (4) an alkyl phenol, (5) a sulfurized alkyl phenol,
and (6) an organic phosphorus acid characterized by at least one
direct carbon-to-phosphorus linkage. Such an organic phosphorus
acid may include those prepared by the treatment of an olefin
polymer (e.g., polyisobutylene having a molecular weight of about
1,000) with a phosphorizing agent such as phosphorus trichloride,
phosphorus heptasulfide, phosphorus pentasulfide, phosphorus
trichloride and sulfur, white phosphorus and a sulfur halide, or
phosphorothioic chloride.
[0100] Suitable salts may include neutral or overbased salts of
magnesium, calcium, or zinc. As a further example, suitable salts
may include magnesium sulfonate, calcium sulfonate, zinc sulfonate,
magnesium phenate, calcium phenate, and/or zinc phenate. See, e.g.,
U.S. Pat. No. 6,482,778. These salts can be used alone or in
combination with another additive. For example, in principle, a
suitable calcium salt may be included in combination with other
additives, such as an organic phosphate in a power transmission
fluid, an additive package, or in a concentrate.
[0101] Oil-soluble neutral metal-containing detergents are those
detergents that contain stoichiometrically equivalent amounts of
metal in relation to the amount of acidic moieties present in the
detergent. Thus, in general the neutral detergents will have a low
basicity when compared to their overbased counterparts. The acidic
materials utilized in forming such detergents include carboxylic
acids, salicylic acids, alkylphenols, sulfonic acids, sulfurized
alkylphenols and the like.
[0102] The term "overbased" in connection with metallic detergents
is used to designate metal salts wherein the metal is present in
stoichiometrically larger amounts than the organic radical. The
commonly employed methods for preparing the overbased salts involve
heating a mineral oil solution of an acid with a stoichiometric
excess of a metal neutralizing agent such as the metal oxide,
hydroxide, carbonate, bicarbonate, or sulfide at a temperature of
about 50.degree. C., and filtering the resultant product. The use
of a "promoter" in the neutralization step to aid the incorporation
of a large excess of metal likewise is known. Examples of compounds
useful as the promoter include phenolic substances such as phenol,
naphthol, alkyl phenol, thiophenol, sulfurized alkylphenol, and
condensation products of formaldehyde with a phenolic substance;
alcohols such as methanol, 2-propanol, octanol, ethylene glycol,
stearyl alcohol, and cyclohexyl alcohol; and amines such as
aniline, phenylene diamine, phenothiazine,
phenyl-beta-naphthylamine, and dodecylamine. A particularly
effective method for preparing the basic salts comprises mixing an
acid with an excess of a basic alkaline earth metal neutralizing
agent and at least one alcohol promoter, and carbonating the
mixture at an elevated temperature such as 60.degree. C. to
200.degree. C.
[0103] Examples of suitable metal-containing detergents include,
but are not limited to, neutral and overbased salts of such
substances as neutral sodium sulfonate, an overbased sodium
sulfonate, a sodium carboxylate, a sodium salicylate, a sodium
phenate, a sulfurized sodium phenate, a lithium sulfonate, a
lithium carboxylate, a lithium salicylate, a lithium phenate, a
sulfurized lithium phenate, a magnesium sulfonate, a magnesium
carboxylate, a magnesium salicylate, a magnesium phenate, a
sulfurized magnesium phenate, a calcium sulfonate, a calcium
carboxylate, a calcium salicylate, a calcium phenate, a sulfurized
calcium phenate, a potassium sulfonate, a potassium carboxylate, a
potassium salicylate, a potassium phenate, a sulfurized potassium
phenate, a zinc sulfonate, a zinc carboxylate, a zinc salicylate, a
zinc phenate, and a sulfurized zinc phenate. Further examples
include a lithium, sodium, potassium, calcium, and magnesium salt
of a hydrolyzed phosphosulfurized olefin having about 10 to about
2,000 carbon atoms or of a hydrolyzed phosphosulfurized alcohol
and/or an aliphatic-substituted phenolic compound having about 10
to about 2,000 carbon atoms. Even further examples include a
lithium, sodium, potassium, calcium, and magnesium salt of an
aliphatic carboxylic acid and an aliphatic substituted
cycloaliphatic carboxylic acid and many other similar alkali and
alkaline earth metal salts of oil-soluble organic acids. A mixture
of a neutral or an overbased salt of two or more different alkali
and/or alkaline earth metals can be used. Likewise, a neutral
and/or an overbased salt of mixtures of two or more different acids
can also be used.
[0104] As is well known, overbased metal detergents are generally
regarded as containing overbasing quantities of inorganic bases,
generally in the form of micro dispersions or colloidal
suspensions. Thus the term "oil-soluble" as applied to metallic
detergents is intended to include metal detergents wherein
inorganic bases are present that are not necessarily completely or
truly oil-soluble in the strict sense of the term, inasmuch as such
detergents when mixed into base oils behave much the same way as if
they were fully and totally dissolved in the oil. Collectively, the
various metallic detergents referred to herein above, are sometimes
called neutral, basic, or overbased alkali metal or alkaline earth
metal-containing organic acid salts.
[0105] Methods for the production of oil-soluble neutral and
overbased metallic detergents and alkaline earth metal-containing
detergents are well known to those skilled in the art, and
extensively reported in the patent literature. See, for example,
U.S. Pat. Nos. 2,001,108; 2,081,075; 2,095,538; 2,144,078;
2,163,622; 2,270,183; 2,292,205; 2,335,017; 2,399,877; 2,416,281;
2,451,345; 2,451,346; 2,485,861; 2,501,731; 2,501,732; 2,585,520;
2,671,758; 2,616,904; 2,616,905; 2,616,906; 2,616,911; 2,616,924;
2,616,925; 2,617,049; 2,695,910; 3,178,368; 3,367,867; 3,496,105;
3,629,109; 3,865,737; 3,907,691; 4,100,085; 4,129,589; 4,137,184;
4,184,740; 4,212,752; 4,617,135; 4,647,387; and 4,880,550.
[0106] The metallic detergents utilized in this invention can, if
desired, be oil-soluble boronated neutral and/or overbased alkali
of alkaline earth metal-containing detergents. Methods for
preparing boronated metallic detergents are described in, for
example, U.S. Pat. Nos. 3,480,548; 3,679,584; 3,829,381; 3,909,691;
4,965,003; and 4,965,004.
[0107] While any effective amount of the metallic detergents may be
used to enhance the benefits of this invention, typically these
effective amounts will range from about 0.01 to about 5.0 wt. % in
the finished fluid, or as a further example, from about 0.05 to
about 3.0 wt. % in the finished fluid.
Organic Phosphorus Additives
[0108] When formulated as a power transmission fluid, or as a
concentrate or as an additive package, a composition of the present
invention can include an organic phosphate. As an example, an
organic phosphate can have the structure:
R.sub.1--X.sub.2--(:X.sub.1)(R.sub.2X.sub.3)--X--R.sub.5 wherein
R.sub.1, and R.sub.2 may independently be substituted or
unsubstituted alkyl, aryl, alkylaryl or cycloalkyl having 1 to 24
carbon atoms and X, X.sub.1, X.sub.2 and X.sub.3 can independently
be sulfur or oxygen. R.sub.1, and R.sub.2 may also contain
substituent heteroatoms, in addition to carbon and hydrogen, such
as chlorine, sulfur, oxygen or nitrogen; R.sub.5 can be derived
from a reactive olefin and can be either
--CH.sub.2--CHR--C(:O)O--R.sub.6; --CH.sub.2--CR.sub.7HR.sub.8; or
R.sub.9--OC(:O)CH.sub.2--CH--C(:O)O--R.sub.10 where R is H or the
same as R.sub.1, R.sub.6, R.sub.7, R.sub.9 and R.sub.10 are the
same as R.sub.1, and R.sub.8 is a phenyl or alkyl or alkenyl
substituted phenyl moiety, the moiety having from 6 to 30 carbon
atoms.
Seal Swell Agents
[0109] In some embodiments, a fluid according to the present
invention can include a seal swell agent, such as used in a
transmission fluid composition, selected from oil-soluble diesters,
oil-soluble sulfones, and mixtures thereof. Generally, the most
suitable diesters include the adipates, azelates, and sebacates of
C.sub.8-C.sub.13 alkanols (or mixtures thereof), and the phthalates
of C.sub.4-C.sub.13 alkanols (or mixtures thereof). Mixtures of two
or more different types of diesters (e.g., dialkyl adipates and
dialkyl azelates, etc.) can also be used. Examples of such
materials include the n-octyl, 2-ethylhexyl, isodecyl, and tridecyl
diesters of adipic acid, azelaic acid, and sebacic acid, and the
n-butyl, isobutyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl,
undecyl, dodecyl, and tridecyl diesters of phthalic acid.
[0110] Other esters which may give generally equivalent performance
are polyol esters. Suitable sulfone seal swell agents are described
in U.S. Pat. Nos. 3,974,081 and 4,029,587. Typically these products
are employed at levels in the range of about 0.1 wt. % to about
10.0 wt. % in the finished transmission fluid. As a further
example, they may be provided in an amount of about 0.25 wt. % to
about 1.0 wt. %.
[0111] Suitable seal swell agents are the oil-soluble dialkyl
esters of (i) adipic acid, (ii) sebacic acid, or (iii) phthalic
acid. The adipates and sebacates should be used in amounts in the
range of from about 1.0 to about 15.0 wt. % in the finished fluid.
In the case of the phthalates, the levels in the transmission fluid
should fall in the range of from about 1.5 to about 10.0 wt. %.
Generally, the higher the molecular weight of the adipate, sebacate
or phthalate, the higher should be the treat rate within the
foregoing ranges.
Viscosity Index Additives
[0112] A fluid composition embodiment of the invention may include
one or more viscosity index improvers. Since the fluid composition
can be used as a fluid transmission or gear lubricant composition,
suitable viscosity index additives include any conventional
viscosity index improvers. In general, exemplary classes of
viscosity index additives are polyisoalkylene compounds and
polymethacrylate compounds, among others. An example of a suitable
polyisoalkylene compound for use as a viscosity index improver
includes polyisobutylene having a weight average molecular weight
ranging from about 700 to about 2,500. Embodiments may include a
mixture of one or more viscosity index improvers of the same or
different molecular weight. Suitable viscosity index improvers may
include styrene-maleic esters, polyalkylmethacrylates, and olefin
copolymer viscosity index improvers. Mixtures of the foregoing
products can also be used as well as dispersant and
dispersant-antioxidant viscosity index improvers.
Additive Package--Diluent
[0113] If a friction modifier compound represented by any of
formula I through VI, or a mixture of any such compounds, is
provided in an additive package (sometimes called a concentrate),
the concentrate includes a suitable carrier diluent is added to
ease blending, solubilizing ingredients, and transporting the
additive package. The diluent oil needs to be compatible with the
base oil and the other ingredients that comprise an additive
package. An additive package can comprise a major amount of an
additive comprised of effective amounts of at least one friction
modifier(s) represented by formula I to VI, a minor amount of a
diluent oil, and, optionally, other desired, compatible additives.
The diluent can be present, for instance, in the concentrate in an
amount of between about 5 to about 20%, although it can vary widely
with application. Generally speaking, less diluent is preferable as
it lowers transportation costs and treat rates.
[0114] Additives used in formulating the compositions described
herein can be blended into base oil individually or in various
sub-combinations. However, it is suitable to blend all of the
components concurrently using an additive concentrate (i.e.,
additives plus a diluent, such as a hydrocarbon solvent). The use
of an additive concentrate takes advantage of the mutual
compatibility afforded by the combination of ingredients when in
the form of an additive concentrate. Also, the use of a concentrate
reduces blending time and lessens the possibility of blending
errors.
Finished Products and Base Oil
[0115] A finished power transmission fluid according to the present
invention typically (but not necessarily always) is formulated with
a major amount of a base oil and a minor amount of an additive
package which includes at least one compound represented by formula
I, II, III, IV, V and/or VI at an effective addition level.
[0116] In one embodiment, a power transmission fluid composition is
formulated to contain a major amount of base oil and an effective
but minor amount of a fluid containing at least one fluid modifier
represented by a formula I to VI. An exemplary power transmission
fluid can contain about 1.0 wt. % to about 25 wt. % of an additive
composition containing a fluid composition according to the present
invention.
[0117] Base oils suitable for use in formulating transmission fluid
compositions according to the invention may be selected from any of
the synthetic or natural oils or mixtures thereof. Natural oils
include animal oils and vegetable oils (e.g., castor oil, lard oil)
as well as mineral lubricating oils such as liquid petroleum oils
and solvent treated or acid-treated mineral lubricating oils of the
paraffinic, naphthenic or mixed paraffinic-naphthenic types. Oils
derived from coal or shale are also suitable. The base oil
typically has a viscosity of, for example, from about 2 to about 15
cSt and, as a further example, from about 2 to about 10 cSt at
100.degree. C. Further, oils derived from a gas-to-liquid process
are also suitable.
[0118] Synthetic oils include hydrocarbon oils such as polymerized
and interpolymerized olefins (e.g., polybutylenes, polypropylenes,
propylene isobutylene copolymers, etc.); polyalphaolefins such as
poly(1-hexenes), poly-(1-octenes), poly(1-decenes), etc. and
mixtures thereof; alkylbenzenes (e.g., dodecylbenzenes,
tetradecylbenzenes, di-nonylbenzenes, di-(2-ethylhexyl)benzenes,
etc.); polyphenyls (e.g., biphenyls, terphenyl, alkylated
polyphenyls, etc.); alkylated diphenyl ethers and alkylated
diphenyl sulfides and the derivatives, analogs and homologs thereof
and the like.
[0119] Alkylene oxide polymers and interpolymers and derivatives
thereof where the terminal hydroxyl groups have been modified by
esterification, etherification, etc., constitute another class of
known synthetic oils that may be used. Such oils are exemplified by
the oils prepared through polymerization of ethylene oxide or
propylene oxide, the alkyl and aryl ethers of these polyoxyalkylene
polymers (e.g., methyl-polyisopropylene glycol ether having an
average molecular weight of about 1000, diphenyl ether of
polyethylene glycol having a molecular weight of about 500-1000,
diethyl ether of polypropylene glycol having a molecular weight of
about 1000-1500, etc.) or mono- and polycarboxylic esters thereof,
for example, the acetic acid esters, mixed C.sub.3-8 fatty acid
esters, or the C.sub.13 oxo acid diester of tetraethylene
glycol.
[0120] Another class of synthetic oils that may be used includes
the esters of dicarboxylic acids (e.g., phthalic acid, succinic
acid, alkyl succinic acids, alkenyl succinic acids, maleic acid,
azelaic acid, suberic acid, sebacic acid, fumaric acid, adipic
acid, linoleic acid dimer, malonic acid, alkyl malonic acids,
alkenyl malonic acids, etc.) with a variety of alcohols (e.g.,
butyl alcohol, hexyl alcohol, dodecyl alcohol, 2-ethylhexyl
alcohol, ethylene glycol, diethylene glycol monoether, propylene
glycol, etc.) Specific examples of these esters include dibutyl
adipate, di(2-ethylhexyl)sebacate, di-n-hexyl fumarate, dioctyl
sebacate, diisooctyl azelate, diisodecyl azelate, dioctyl
phthalate, didecyl phthalate, dieicosyl sebacate, the 2-ethylhexyl
diester of linoleic acid dimer, the complex ester formed by
reacting one mole of sebacic acid with two moles of tetraethylene
glycol and two moles of 2-ethylhexanoic acid and the like.
[0121] Esters useful as synthetic oils also include those made from
C.sub.5 to C.sub.12 monocarboxylic acids and polyols and polyol
ethers such as neopentyl glycol, trimethylol propane,
pentaerythritol, dipentaerythritol, tripentaerythritol, etc.
[0122] Hence, the base oil used which may be used to make the
transmission fluid compositions as described herein may be selected
from any of the base oils in Groups I-V as specified in the
American Petroleum Institute (API) Base Oil Interchangeability
Guidelines.
[0123] Such base oil groups are as follows: TABLE-US-00001 Base Oil
Saturates Viscosity Group.sup.1 Sulfur (wt. %) (wt. %) Index Group
I >0.03 and/or <90 80 to 120 Group II .ltoreq.0.03 And
.gtoreq.90 80 to 120 Group III .ltoreq.0.03 And .gtoreq.90
.gtoreq.120 Group IV All polyalphaolefins (PAOs) Group V all others
not included in Groups I-IV .sup.1Groups I-III are mineral oil base
stocks.
[0124] As set forth above, the base oil may be a poly-alpha-olefin
(PAO). Typically, the poly-alpha-olefins are derived from monomers
having from about 4 to about 30, or from about 4 to about 20, or
from about 6 to about 16 carbon atoms. Examples of useful PAOs
include those derived from octene, decene, mixtures thereof, and
the like. PAOs may have a viscosity of from about 2 to about 15, or
from about 3 to about 12, or from about 4 to about 8 cSt at
100.degree. C. Examples of PAOs include 4 cSt at 100.degree. C.
poly-alpha-olefins, 6 cSt at 100.degree. C. poly-alpha-olefins, and
mixtures thereof. Mixtures of mineral oil with the foregoing
poly-alpha-olefins may be used.
[0125] The base oil may be an oil derived from Fischer-Tropsch
synthesized hydrocarbons. Fischer-Tropsch synthesized hydrocarbons
are made from synthesis gas containing H.sub.2 and CO using a
Fischer-Tropsch catalyst. Such hydrocarbons typically require
further processing in order to be useful as the base oil. For
example, the hydrocarbons may be hydroisomerized using processes
disclosed in U.S. Pat. No. 6,103,099 or 6,180,575; hydrocracked and
hydroisomerized using processes disclosed in U.S. Pat. No.
4,943,672 or 6,096,940; dewaxed using processes disclosed in U.S.
Pat. No. 5,882,505; or hydroisomerized and dewaxed using processes
disclosed in U.S. Pat. No. 6,013,171; 6,080,301; or 6,165,949.
[0126] Unrefined, refined and rerefined oils, either natural or
synthetic (as well as mixtures of two or more of any of these) of
the type disclosed hereinabove can be used in the base oils.
Unrefined oils are those obtained directly from a natural or
synthetic source without further purification treatment. For
example, a shale oil obtained directly from retorting operations, a
petroleum oil obtained directly from primary distillation or ester
oil obtained directly from an esterification process and used
without further treatment would be an unrefined oil. Refined oils
are similar to the unrefined oils except they have been further
treated in one or more purification steps to improve one or more
properties. Many such purification techniques are known to those
skilled in the art such as solvent extraction, secondary
distillation, acid or base extraction, filtration, percolation,
etc. Rerefined oils are obtained by processes similar to those used
to obtain refined oils applied to refined oils which have been
already used in service. Such rerefined oils are also known as
reclaimed or reprocessed oils and often are additionally processed
by techniques directed to removal of spent additives, contaminants,
and oil breakdown products.
[0127] In selecting any of the optional additives, it is important
to ensure that the selected component(s) is/are soluble or stably
dispersible in the additive package and finished automatic
transmission fluid ("ATF") composition, are compatible with the
other components of the composition, and do not interfere
significantly with the performance properties of the composition,
such as the extreme pressure, antiwear, friction, anti-shudder,
viscosity and/or shear stability properties, needed or desired, as
applicable, in the overall finished composition.
[0128] In general, the ancillary additive components are employed
in the oil in minor amounts sufficient to improve the performance
characteristics and properties of the base fluid. The amounts will
thus vary in accordance with such factors as the viscosity
characteristics of the base fluid employed, the viscosity
characteristics desired in the finished fluid, the service
conditions for which the finished fluid is intended, and the
performance characteristics desired in the finished fluid.
[0129] However, generally speaking, the following generally
concentrations (weight percent unless otherwise indicated) of the
additional components in the base fluids are illustrative.
[0130] Additives are blended into a base oil in their respective
amounts which amounts are sufficient to provide their expected
performance. Representative effective amounts are illustrated as
follows: TABLE-US-00002 Component wt % Dispersant 1-20 Viscosity
Index Improver 0.1-25 Antioxidant 0.01-10 Corrosion Inhibitor
0.01-2 Detergents and Rust 0.01-5 Inhibitors Seal-swell Agent
0.1-10 Anti-foam Agent .sup. 0.001-0.1.sup. Anti-wear Agents
0.01-0.5 Other Friction Modifiers 0.01-5 Lubricating Base Oil
Balance
[0131] It will be appreciated that the individual components
employed can be separately blended into the base fluid or can be
blended therein in various subcombinations, if desired. Ordinarily,
the particular sequence of such blending steps is not crucial.
Moreover, such components can be blended in the form of separate
solutions in a diluent. It is preferable, however, to blend the
additive components used in the form of a concentrate, as this
simplifies the blending operations, reduces the likelihood of
blending errors, and takes advantage of the compatibility and
solubility characteristics afforded by the overall concentrate.
[0132] Additive concentrates can thus be formulated to contain all
of the additive components and if desired, some of the base oil
component, in amounts proportioned to yield finished fluid blends
consistent with the concentrations described above. In most cases,
the additive concentrate will contain one or more diluents such as
light mineral oils, to facilitate handling and blending of the
concentrate. Thus concentrates containing up to about 50 wt. % of
one or more diluents or solvents can be used, provided the solvents
are not present in amounts that interfere with the low and high
temperature and flash point characteristics and the performance of
the finished power transmission fluid composition. In this regard,
the additive components used pursuant to this invention may be
selected and proportioned such that an additive concentrate or
package formulated from such components will have a flash point of
about 170.degree. C. or above, using the ASTM D-92 test
procedure.
[0133] Power transmission fluids of the embodiments herein are
formulated to provide enhanced extreme pressure properties for
applications where metal-to-metal contact is made under high
pressures, e.g., pressures in excess of 2 GPa. Such fluids are
suitable for automatic and manual transmissions such as step
automatic transmissions, continuously variable transmissions,
automated manual transmissions, and dual clutch transmissions. High
metal-to-metal contact pressures such as those found in automotive
transmissions, for example, may cause damage to transmission parts
if a fluid is used that does not possess sufficient properties,
including extreme pressure protection characteristics. Power
transmission fluid compositions as described herein have improved
performance characteristics. Further, the power transmission fluids
of the present disclosure also are suitable for use in
transmissions with an electronically controlled converter clutch, a
slipping torque converter, a lock-up torque converter, a starting
clutch, and/or one or more shifting clutches. Such transmissions
include four-, five-, six-, and seven-speed transmissions, and
continuously variable transmissions (chain, belt, or disk type).
They also may be used in gear applications, such as industrial gear
applications and automotive gear applications. Gear-types may
include, but are not limited to, spur, spiral bevel, helical,
planetary, and hypoid gears. They may be used in axles, transfer
cases, and the like. Further, they may also be useful in
metalworking applications.
[0134] The so-called LFW-1 test involves measuring friction between
a rotating steel ring against a stationary block having a friction
material of interest at a given load and temperature. A test cycle
involves acceleration and deceleration modes between zero and a
maximum speed of 0.5 m/sec. The X-axis and Y-axis in the graphs in
FIG. 1 represent speed and coefficient of friction (.mu.),
respectively. End-points on the curves, being close to zero speed,
are regarded as static coefficient of friction (.mu..sub.sta),
while the friction in mid-point (maximum speed) is regarded as
dynamic coefficient of friction (.mu..sub.dyn). Surprisingly, a
fluid according the invention exhibits a reduced change (delta) in
the dynamic coefficient of friction, .mu..sub.d, between its fresh
versus an aged condition in comparison to conventional fluids.
Samples having .mu..sub.s/.mu..sub.d values higher than one can be
said to exhibit shudder problem when used as a power transmission
fluid; for example, a fluid according to the invention that has a
fresh oil .mu..sub.s/.mu..sub.d value in a secure shudder-free
range (.about.0.9) can manifest a low delta in
.mu..sub.s/.mu..sub.d, while showing improved (higher) dynamic
coefficient of friction on aging (FMs 8, 11, 12, 13, 14 in Table
1). The smaller the delta .mu..sub.s/.mu..sub.d between fresh and
aged, the better is the friction durability and if .mu..sub.d
increases it can translate to more effective power transmitting
capability in dynamic mode upon aging.
[0135] As shown in FIG. 1, there is less chance of a change overall
in the dynamic coefficient of friction for a power transmission
fluid B according to the invention versus a conventional
formulation A when the LFW1 test was conducted on samples that are
subjected to 296 hours of heating at 170.degree. C. under an air
flow of 10 L/minute. Frictional benefits of using the compositions
described in this invention are illustrated in FIG. 1 that
graphically shows a LFW-1 friction test comparison between fresh
and aged oils. Oil A contains oleic acid/TEPA-derived bisacylamide
whereas, Oil B contains oleic acid/TETA-derived imidazoline reacted
with 750 molecular weight PIBSA. Both friction modifiers ("FMs")
are at a level to provide 950 ppm of nitrogen to the finished
fluid.
[0136] A fluid according to the present invention can be formulated
for use in a power transmitting apparatus, including a power
transmission fluid, such as an ATF, in a transmission. An aspect of
the present invention is a transmission. Exemplary transmissions
include those described in "Transmission and Driveline Design", SAE
Paper Number SP-108, Society of Automotive Engineers, Warrendale
Pa. 1995; "Design of Practices: Passenger Car Automotive
Transmissions", The Third Edition, SAE Publication # AE-18, Society
of Automotive Engineers, Warrendale Pa. 1994; and "Automotive
Transmission Advancements", SAE Paper Number SP-854, Society of
Automotive Engineers, Warrendale Pa. 1991.
[0137] An aspect of the present invention includes a transmission
containing a power transmission fluid, provided the fluid contains,
as a fluid modifier(s), at least one compound represented by a
formula I, II, III, IV, V or VI, or a mixture of compounds of any
of these formulas. For example, a suitable mixture may include a
compound represented by a formula I and a compound represented by
at least one of formula II, III, IV, V or VI. The transmission
embodiment includes a belt, chain, or disk-type continuously
variable transmission, a 4-, 5-, 6-, or 7-speed automatic
transmission, a manual transmission, a dual clutch
transmission.
[0138] A further aspect of the invention is a vehicle comprising an
engine and a transmission, the transmission including a power
transmission fluid as above-described. A vehicle can contain a
differential, and therefore in another embodiment, a vehicle
contains a differential including a lubricant containing a fluid
composition as above-described. Vehicle includes without limitation
a truck, an automobile, and a piece of mechanized farm equipment,
such as a tractor or reaper.
EXAMPLES
[0139] Illustrative compositions suitable for use in the practice
of this invention are presented in the following Examples, wherein
all parts and percentages are by weight unless specified
otherwise.
Example 1
[0140] Reaction of isostearic acid with triethylenetetramine (TETA)
was performed in a 2 L 3-neck round bottom flask, equipped with a
pressure equilibrated addition funnel, distillation condenser, and
a mechanical stirrer. To stirred isostearic acid (405.3 g), TETA
(153.0 g) was added drop-wise at 75.degree. C. Addition continued
slowly below 100.degree. C. until the reaction is no longer
exothermic. After addition of the remaining amine, vacuum was
applied (28'' Hg) with caution and temperature was increased
gradually to 150.degree. C. The mixture was stirred under vacuum
for 19 hours. The reaction was expected to form 44.9 g. of water.
Total of 48.2 g of volatile material was collected in a dry-ice
trap.
[0141] Following analysis, these results were obtained for the
product: TAN (D-664) 3.1 mg KOH/g; TBN (D-2869) 262.8 mg KOH/g; KV
(100) 20.22 cSt; N:10.97% (Calc'd: 11.41%). IR (cm.sup.-1): 1660,
1613, 1459, 1248, 1004, 726.
Example 2
[0142] Reaction product of Example 1 (67.2 g), a diluent oil (76.2
g) and C20-24 alkyl succinic anhydride (87.5 g) from Dixie Chemical
Company were charged into a 500 mL round bottom flask equipped with
a distillation condenser and a mechanical stirrer. The mixture was
stirred at 100.degree. C. under vacuum (28'' Hg) for 1 hour.
Analysis of the resulting product gave: TAN (D-664) 31.1 mg KOH/g;
TBN (D-2869) 37.6 mg KOH/g; N, 3.18% (Calc'd: 3.38%). IR
(cm.sup.-1): 1771, 1705, 1649.
Example 3
[0143] Reaction product of Example 1 (55.33 g), a diluent oil
(55.91 g) and 200 mol. wt. PIBSA (56.29 g) having activity of 3.34
meq/g were reacted under conditions described in Example 2.
Analysis of the resulting product gave TAN (D-664) 28.8 mg KOH/g;
TBN (D-2869) 43.5 mg KOH/g; N, 3.61% (Calc'd: 3.68%). IR
(cm.sup.-1): 1778, 1705, 1642.
Example 4
[0144] Table 1 shows LFW-1 results for fresh and aged oils. An
embodiment from the broad composition described hereinabove was
used to evaluate the following friction modifiers in LFW-1 Friction
Test as shown in Table 1. Data are plotted in FIG. 1.
[0145] Table 1 shows a number of examples of oil-containing fluid
formulations according to the present invention that provide good
fresh oil friction characteristics (.mu..sub.s/.mu..sub.d<about
1.0) that undergo much less change after oxidation compared to a
conventional formulation. TABLE-US-00003 TABLE I Molar New Aged
Delta Delta REACTANTS Ratios .mu..sub.s/.mu..sub.d .mu..sub.s
.mu..sub.d .mu..sub.s/.mu..sub.d .mu..sub.s .mu..sub.d
.mu..sub.s/.mu..sub.d*1000 .mu..sub.d*1000 FM1
OA:TETA:C.sub.20-24ASA 4:3:5 0.8387 0.1611 0.1921 1.0065 0.2010
0.1997 16.78 7.62 FM2 OA:TETA:C.sub.20-24ASA 4:3:3.7 0.8294 0.1561
0.1882 1.0184 0.2037 0.2000 18.9 11.82 FM3 OA:TETA:C.sub.20-24ASA
4:3:2.5 0.7916 0.1441 0.1820 1.0316 0.2073 0.2009 24 18.91 FM4
OA:TETA:200MW PIBSA 4:3:5 0.8207 0.1572 0.1915 1.0493 0.2160 0.2059
22.86 14.31 FM5 OA:TETA:350MW PIBSA 4:3:5 0.8832 0.1773 0.2007
1.0443 0.2159 0.2067 16.11 5.99 FM6 OA:TETA:750MW PIBSA 4:3:5
0.8957 0.1793 0.2002 1.0438 0.2149 0.2059 14.81 5.70 FM7
ISA:TETA:200MW PIBSA 4:3:5 0.9624 0.2183 0.2268 1.0330 0.2345
0.2270 7.06 0.18 FM8 ISA:TETA:200MW PIBSA 4:3:2.5 0.9008 0.1941
0.2125 1.0247 0.2184 0.2131 12.39 -2.34 FM9 ISA:TETA:750MW PIBSA
4:3:5 0.9768 0.2171 0.2223 1.0278 0.2299 0.2237 5.1 1.43 FM10
ISA:TETA:750MW PIBSA 4:3:2.5 0.9245 0.2022 0.2187 1.0181 0.2278
0.2238 9.36 5.04 Ref1 0.8241 0.1460 0.1772 1.0513 0.2102 0.1999
22.72 22.73 FM11 ISA:TETA:C.sub.20-24ASA 4:3:2.5 0.8821 0.1806
0.2047 0.9911 0.2018 0.2036 10.9 -1.13 FM12 ISA:TETA:C.sub.20-24ASA
4:3:5 0.9152 0.1900 0.2076 0.9807 0.1977 0.2016 6.55 -6.01 FM13
ISA:TETA:C.sub.18ASA 4:3:2.5 0.8940 0.1818 0.2034 0.9867 0.1960
0.1986 9.27 -4.71 FM14 ISA:TETA:C.sub.18ASA 4:3:5 0.8677 0.1759
0.2027 0.9982 0.2002 0.2006 13.05 -2.16 FM15 ISA:TETA:C.sub.12ASA
4:3:2.5 0.9573 0.2073 0.2165 1.0201 0.2107 0.2065 6.28 -10.00 FM16
ISA:TETA:C.sub.12ASA 4:3:5 0.9070 0.1912 0.2108 1.0184 0.2093
0.2055 11.14 -5.29 Ref2 0.8369 0.1484 0.1773 1.0098 0.1976 0.1957
17.28 18.44
[0146] In Table 1, OA is oleic acid; ISO is isostearic acid; TETA
is triethylene tetramine; and C.sub.20-24-ASA is an alkyl succinic
anhydride where the alkyl group is an isomerized form of a mixture
of C.sub.20 to C.sub.24 alpha-olefins. PIBSA refers to
polyisobutylene succinic anhydride and the designations 200MW,
350MW, and 750MW relate the molecular weights (amu).
[0147] Reference 1 and Reference 2 use Ethomeen T-12, which is a
commercially available ethoxylated tallowalkylamine from Akzo Nobel
at equal nitrogen content.
[0148] The friction modifiers (FM's) reported in Table 1 are
prepared by a two-stage process. In a first stage, a fatty acid is
reacted with a polyamine, and in a second stage, the first stage
product(s) are post-treated with an alkyl succinic anhydride. More
particularly, a first stage product (OL/TETA or ISA/TETA) is
post-treated with an alkyl succinic anhydride. The reaction
stoichiometry is presented in Table 1. The various alkyl succinic
anhydrides are also presented in Table 1. Example 1 describes
suitable reaction conditions for the first stage. The FM9 is
prepared by applying the conditions and procedures described in
Example 1 for the first stage, and in Example 2 for the second
stage. The FM12 is prepared by applying the conditions and
procedures described in Example 1 for the first stage, and in
Example 3 for the second stage. The other FM's in Table 1 are
prepared using the same protocols as in Examples 1 and 2.
[0149] FM1 through Ref 1 provide 970 ppm nitrogen to the finished
fluid. The duration of stability against oxidation for these oils
is tested for 198 hours at 170.degree. C. with bubbling air at a
rate of 10 L/h.
[0150] The duration of stability against oxidation for oils
containing FM11 through Ref 2 were different in that the test was
conducted for only 120 hours and the nitrogen contribution from
these friction modifiers was 375 ppm.
[0151] For instance, values for .mu..sub.s/.mu..sub.d of a friction
modifier composition (such as FM-1 through FM-16) generally can be
up to about 1.0, and as a further example may be less than about
0.9, while still avoiding shudder problems and exhibiting
sufficient durability against oxidation.
[0152] The dynamic coefficient of friction, .mu..sub.d, is known to
relate to effectives of torque transfer, and therefore to fuel
efficiency. High numerical values for this parameter (.mu..sub.d)
are suitable. In terms of friction durability, change in these
parameters resulting from aging of the oil should be minimal. High
delta values indicate that oil loses its initial friction
characteristics as a result of thermal and oxidative stress.
[0153] At numerous places throughout this specification, reference
has been made to a number of U.S. Patents, European Patent
Applications (published), PCT International patent publications,
and literature references. All such cited documents are expressly
incorporated in full into this disclosure as if fully set forth
herein.
[0154] As used throughout the specification and claims, "a" and/or
"an" may refer to one or more than one. Unless otherwise indicated,
all numbers expressing quantities of ingredients, properties such
as molecular weight, percent, ratio, reaction conditions, and so
forth used in the specification and claims are to be understood as
being modified in all instances by the term "about." Accordingly,
unless indicated to the contrary, the numerical parameters set
forth in the specification and claims are approximations that may
vary depending upon the desired properties sought to be obtained by
the present invention. At the very least, and not as an attempt to
limit the application of the doctrine of equivalents to the scope
of the claims, each numerical parameter should at least be
construed in light of the number of reported significant digits and
by applying ordinary rounding techniques. Notwithstanding that the
numerical ranges and parameters setting forth the broad scope of
the invention are approximations, the numerical values set forth in
the specific examples are reported as precisely as possible. Any
numerical value, however, inherently contains certain errors
necessarily resulting from the standard deviation found in their
respective testing measurements.
[0155] While the present invention has been principally
demonstrated hereinabove as a power transmitting fluid for
transmissions, it is contemplated that the benefits of the fluid
embodiment are similarly applicable to other power transmitting
fluids included within the scope of the present invention are gear
oils, hydraulic fluids, heavy duty hydraulic fluids, industrial
oils, power steering fluids, pump oils, tractor fluids, and
universal tractor fluids, and apparatus embodiments include gears,
hydraulic mechanisms, power steering devices, pumps and the like
incorporating a fluid according to the invention.
[0156] Other embodiments of the present invention will be apparent
to those skilled in the art from consideration of the
specification, Figure and practice of the invention disclosed
herein. It is intended that the specification and examples be
considered as exemplary only, with a true scope and spirit of the
invention being indicated by the following claims.
* * * * *